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* Re: OIDs, CTIDs, updateable cursors and friends
@ 2004-02-18 15:27 Dave Page <[email protected]>
0 siblings, 1 reply; 262+ messages in thread
From: Dave Page @ 2004-02-18 15:27 UTC (permalink / raw)
To: Shachar Shemesh <[email protected]>; +Cc: pgsql-hackers; PostgreSQL OLE DB development <[email protected]>
> -----Original Message-----
> From: Shachar Shemesh [mailto:[email protected]]
> Sent: 18 February 2004 14:56
> To: Dave Page
> Cc: Hackers; PostgreSQL OLE DB development
> Subject: Re: [HACKERS] OIDs, CTIDs, updateable cursors and friends
>
> I'll have a look at that. How would updateable cursors do it?
> By locking the row?
Dunno, we don't have them!
> So, basically, I would not be able to update a table that has
> no primary key?
Yes, unless you feel back to the value matching type update.
Realistically though, how can anyone expect to edit data successfully
unless they have defined a key to identify rows with? Whilst it's nice
to get it to work 100% of the time no matter how brain dead the schema
it's not that practical.
> What happens if I check how many would be updated, and get
> "1" as a result. I then actually do it, but between asking
> and performing, someone added a second row that matches the criteria?
It'll update both rows unless you do it in one transaction.
> But what if someone else changes some of the known values of my row?
The update will fail to find any rows. This is almost certainly what
happens when MS Access starts pinting #DELETED# in rows of a linked
table.
> Ok, it seems to me there are several options here.
> 1. Find out which is the primary key for the table. What
> happens if the primary key is a multi-row thing? What happens
> if there is no primary key?
I guess you mean multicolumn? No different, you just need all columns in
your WHERE clause. If there is no pkey (and I would be inclined to say
if there is none in the user's query and not try to add it yourself)
then you fail with an error.
> 2. If I'm in a transaction, use OID for the insert after
> checking with a select that I'm only affecting one row. If
> I'm not in a transaction - perform the update in a generated
> transaction, and roll it back if there is more than one row affected.
>
> I like 1 better, frankly. Dillemas dillemas dillemas.
1 is definitely better and is the only way that is guaranteed to be
safe. Thinking about it more, that is almost certainly the position a
driver should take. In pgAdmin we can afford a little artistic licence
(no pun intended) because no one will be using pgAdmin as a driver to
connect another program to a database, plus we can ask the user what
action to take if we don't know if the result will be exactly what was
intended. You do not have that luxury in a driver of course.
Regards, Dave
^ permalink raw reply [nested|flat] 262+ messages in thread
* Re: OIDs, CTIDs, updateable cursors and friends
@ 2004-02-18 16:14 Brett Schwarz <[email protected]>
parent: Dave Page <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Brett Schwarz @ 2004-02-18 16:14 UTC (permalink / raw)
To: Dave Page <[email protected]>; Shachar Shemesh <[email protected]>; +Cc: pgsql-hackers; PostgreSQL OLE DB development <[email protected]>
> > Ok, it seems to me there are several options here.
> > 1. Find out which is the primary key for the
> table. What
> > happens if the primary key is a multi-row thing?
> What happens
> > if there is no primary key?
>
> I guess you mean multicolumn? No different, you just
> need all columns in
> your WHERE clause. If there is no pkey (and I would
> be inclined to say
> if there is none in the user's query and not try to
> add it yourself)
> then you fail with an error.
>
> > 2. If I'm in a transaction, use OID for the insert
> after
> > checking with a select that I'm only affecting one
> row. If
> > I'm not in a transaction - perform the update in a
> generated
> > transaction, and roll it back if there is more
> than one row affected.
> >
> > I like 1 better, frankly. Dillemas dillemas
> dillemas.
>
> 1 is definitely better and is the only way that is
> guaranteed to be
> safe. Thinking about it more, that is almost
> certainly the position a
> driver should take. In pgAdmin we can afford a
> little artistic licence
> (no pun intended) because no one will be using
> pgAdmin as a driver to
> connect another program to a database, plus we can
> ask the user what
> action to take if we don't know if the result will
> be exactly what was
> intended. You do not have that luxury in a driver of
> course.
Just as another datapoint, pgaccess does the same
thing (finding the pkey(s), and using those to
uniquely identify the row). It is kind of a PITA, but
as Dave says, it's the best way to do this.
HTH,
--brett
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^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
* [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms
@ 2023-01-17 04:38 Andres Freund <[email protected]>
0 siblings, 0 replies; 262+ messages in thread
From: Andres Freund @ 2023-01-17 04:38 UTC (permalink / raw)
Until now we used struct timespec on all platforms but windows. Using struct
timespe causes a fair bit of memory (struct timeval is 16 bytes) and runtime
overhead (much more complicated additions). Instead we can convert the time to
nanoseconds in INSTR_TIME_SET_CURRENT(), making the remaining operations
cheaper.
Representing time as int64 nanoseconds provides sufficient range, ~292 years
relative to a starting point (depending on clock source, relative to the unix
epoch or the system's boot time). That'd not be sufficient for calendar time
stored on disk, but is plenty for runtime interval time measurement.
On windows instr_time already is represented as cycles. It might make sense to
represent time as cycles on other platforms as well, as using cycle
acquisition instructions like rdtsc directly can reduce the overhead of time
acquisition substantially. This could be done in a fairly localized manner as
the code stands after this commit.
Because the windows and non-windows paths are now more similar, use a common
set of macros. To make that possible, most of the use of LARGE_INTEGER had to
be removed, which looks nicer anyway.
To avoid users of the API relying on the integer representation, we wrap the
64bit integer inside struct struct instr_time.
Author: Andres Freund <[email protected]>
Author: Lukas Fittl <[email protected]>
Author: David Geier <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
src/include/portability/instr_time.h | 162 ++++++++++++++-------------
1 file changed, 86 insertions(+), 76 deletions(-)
diff --git a/src/include/portability/instr_time.h b/src/include/portability/instr_time.h
index 9ea1a68bd94..c0ed491395d 100644
--- a/src/include/portability/instr_time.h
+++ b/src/include/portability/instr_time.h
@@ -34,6 +34,8 @@
*
* INSTR_TIME_GET_MICROSEC(t) convert t to uint64 (in microseconds)
*
+ * INSTR_TIME_GET_NANOSEC(t) convert t to uint64 (in nanoseconds)
+ *
* Note that INSTR_TIME_SUBTRACT and INSTR_TIME_ACCUM_DIFF convert
* absolute times to intervals. The INSTR_TIME_GET_xxx operations are
* only useful on intervals.
@@ -54,8 +56,32 @@
#ifndef INSTR_TIME_H
#define INSTR_TIME_H
+
+/*
+ * We store interval times as an int64 integer on all platforms, as int64 is
+ * cheap to add/subtract, the most common operation for instr_time. The
+ * acquisition of time and converting to specific units of time is platform
+ * specific.
+ *
+ * To avoid users of the API relying on the integer representation, we wrap
+ * the 64bit integer in a struct.
+ */
+typedef struct instr_time
+{
+ int64 ticks; /* in platforms specific unit */
+} instr_time;
+
+
+/* helpers macros used in platform specific code below */
+
+#define NS_PER_S INT64CONST(1000000000)
+#define NS_PER_MS INT64CONST(1000000)
+#define NS_PER_US INT64CONST(1000)
+
+
#ifndef WIN32
+
/* Use clock_gettime() */
#include <time.h>
@@ -80,93 +106,43 @@
#define PG_INSTR_CLOCK CLOCK_REALTIME
#endif
-typedef struct timespec instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_clock_gettime_ns(void)
+{
+ instr_time now;
+ struct timespec tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).tv_nsec == 0 && (t).tv_sec == 0)
+ clock_gettime(PG_INSTR_CLOCK, &tmp);
+ now.ticks = tmp.tv_sec * NS_PER_S + tmp.tv_nsec;
-#define INSTR_TIME_SET_ZERO(t) ((t).tv_sec = 0, (t).tv_nsec = 0)
+ return now;
+}
-#define INSTR_TIME_SET_CURRENT(t) ((void) clock_gettime(PG_INSTR_CLOCK, &(t)))
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_clock_gettime_ns())
-#define INSTR_TIME_ADD(x,y) \
- do { \
- (x).tv_sec += (y).tv_sec; \
- (x).tv_nsec += (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (t).ticks)
-#define INSTR_TIME_SUBTRACT(x,y) \
- do { \
- (x).tv_sec -= (y).tv_sec; \
- (x).tv_nsec -= (y).tv_nsec; \
- /* Normalize */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- } while (0)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- do { \
- (x).tv_sec += (y).tv_sec - (z).tv_sec; \
- (x).tv_nsec += (y).tv_nsec - (z).tv_nsec; \
- /* Normalize after each add to avoid overflow/underflow of tv_nsec */ \
- while ((x).tv_nsec < 0) \
- { \
- (x).tv_nsec += 1000000000; \
- (x).tv_sec--; \
- } \
- while ((x).tv_nsec >= 1000000000) \
- { \
- (x).tv_nsec -= 1000000000; \
- (x).tv_sec++; \
- } \
- } while (0)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).tv_sec) + ((double) (t).tv_nsec) / 1000000000.0)
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).tv_sec * 1000.0) + ((double) (t).tv_nsec) / 1000000.0)
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- (((uint64) (t).tv_sec * (uint64) 1000000) + (uint64) ((t).tv_nsec / 1000))
#else /* WIN32 */
+
/* Use QueryPerformanceCounter() */
-typedef LARGE_INTEGER instr_time;
+/* helper for INSTR_TIME_SET_CURRENT */
+static inline instr_time
+pg_query_performance_counter(void)
+{
+ instr_time now;
+ LARGE_INTEGER tmp;
-#define INSTR_TIME_IS_ZERO(t) ((t).QuadPart == 0)
+ QueryPerformanceCounter(&tmp);
+ now.ticks = tmp.QuadPart;
-#define INSTR_TIME_SET_ZERO(t) ((t).QuadPart = 0)
-
-#define INSTR_TIME_SET_CURRENT(t) QueryPerformanceCounter(&(t))
-
-#define INSTR_TIME_ADD(x,y) \
- ((x).QuadPart += (y).QuadPart)
-
-#define INSTR_TIME_SUBTRACT(x,y) \
- ((x).QuadPart -= (y).QuadPart)
-
-#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
- ((x).QuadPart += (y).QuadPart - (z).QuadPart)
-
-#define INSTR_TIME_GET_DOUBLE(t) \
- (((double) (t).QuadPart) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MILLISEC(t) \
- (((double) (t).QuadPart * 1000.0) / GetTimerFrequency())
-
-#define INSTR_TIME_GET_MICROSEC(t) \
- ((uint64) (((double) (t).QuadPart * 1000000.0) / GetTimerFrequency()))
+ return now;
+}
static inline double
GetTimerFrequency(void)
@@ -177,11 +153,45 @@ GetTimerFrequency(void)
return (double) f.QuadPart;
}
+#define INSTR_TIME_SET_CURRENT(t) \
+ ((t) = pg_query_performance_counter())
+
+#define INSTR_TIME_GET_NANOSEC(t) \
+ ((int64) (((double) (t).ticks * NS_PER_S) / GetTimerFrequency()))
+
#endif /* WIN32 */
-/* same macro on all platforms */
+
+/*
+ * Common macros
+ */
+
+#define INSTR_TIME_IS_ZERO(t) ((t).ticks == 0)
+
+
+#define INSTR_TIME_SET_ZERO(t) ((t).ticks = 0)
#define INSTR_TIME_SET_CURRENT_LAZY(t) \
(INSTR_TIME_IS_ZERO(t) ? INSTR_TIME_SET_CURRENT(t), true : false)
+
+#define INSTR_TIME_ADD(x,y) \
+ ((x).ticks += (y).ticks)
+
+#define INSTR_TIME_SUBTRACT(x,y) \
+ ((x).ticks -= (y).ticks)
+
+#define INSTR_TIME_ACCUM_DIFF(x,y,z) \
+ ((x).ticks += (y).ticks - (z).ticks)
+
+
+#define INSTR_TIME_GET_DOUBLE(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_S)
+
+#define INSTR_TIME_GET_MILLISEC(t) \
+ ((double) INSTR_TIME_GET_NANOSEC(t) / NS_PER_MS)
+
+#define INSTR_TIME_GET_MICROSEC(t) \
+ (INSTR_TIME_GET_NANOSEC(t) / NS_PER_US)
+
#endif /* INSTR_TIME_H */
--
2.38.0
--vt42kbp2j7rjcapp
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0003-instr_time-Add-INSTR_TIME_SET_SECONDS-INSTR_TIME_.patch"
^ permalink raw reply [nested|flat] 262+ messages in thread
end of thread, other threads:[~2023-01-17 04:38 UTC | newest]
Thread overview: 262+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2004-02-18 15:27 Re: OIDs, CTIDs, updateable cursors and friends Dave Page <[email protected]>
2004-02-18 16:14 ` Brett Schwarz <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
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2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
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2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
2023-01-17 04:38 [PATCH v8 2/5] instr_time: Represent time as an int64 on all platforms Andres Freund <[email protected]>
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