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* Re: [PATCH] SortSupport for macaddr type
@ 2017-03-02 22:39 Julien Rouhaud <[email protected]>
0 siblings, 1 reply; 134+ messages in thread
From: Julien Rouhaud @ 2017-03-02 22:39 UTC (permalink / raw)
To: Brandur Leach <[email protected]>; +Cc: pgsql-hackers
On Tue, Feb 28, 2017 at 08:58:24AM -0800, Brandur Leach wrote:
> Hi Julien,
>
Hello Brandur,
> Thanks for the expedient reply, even after I'd dropped the
> ball for so long :)
:)
> Cool! I just re-read my own comment a few days later and I
> think that it still mostly makes sense, but definitely open
> to other edits if anyone else has one.
>
Ok.
> > One last thing, I noticed that you added:
> >
> > +static int macaddr_internal_cmp(macaddr *a1, macaddr *a2);
> >
> > but the existing function is declared as
> >
> > static int32
> > macaddr_internal_cmp(macaddr *a1, macaddr *a2)
> >
> > I'd be in favor to declare both as int.
>
> Great catch! I have no idea how I missed that. I've done as
> you suggested and made them both "int", which seems
> consistent with SortSupport implementations elsewhere.
>
Great.
> > After this, I think this patch will be ready for committer.
>
> Excellent! I've attached a new (and hopefully final)
> version of the patch.
>
> Two final questions about the process if you'd be so kind:
>
> * Should I change the status on the Commitfest link [1] or
> do I leave that to you (or someone else like a committer)?
>
This is is done by the reviewer, after check of the last patch version. I just
changed the status to ready for committer!
> * I've been generating a new OID value with the
> `unused_oids` script, but pretty much every time I rebase
> I collide with someone else's addition and need to find a
> new one. Is it better for me to pick an OID in an exotic
> range for my final patch, or that a committer just finds
> a new one (if necessary) as they're putting it into
> master?
I think picking the value with unused_oids as you dd is the right thing to do.
As Robert said, if this oid is used in another patch in the meantime, updating
it at commit time is not a big deal. Moreover, this patch will require a
catversion bump, which is meant to be done by the committer.
--
Julien Rouhaud
http://dalibo.com - http://dalibo.org
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^ permalink raw reply [nested|flat] 134+ messages in thread
* Re: [PATCH] SortSupport for macaddr type
@ 2017-03-03 02:27 Neha Khatri <[email protected]>
parent: Julien Rouhaud <[email protected]>
0 siblings, 1 reply; 134+ messages in thread
From: Neha Khatri @ 2017-03-03 02:27 UTC (permalink / raw)
To: Julien Rouhaud <[email protected]>; +Cc: Brandur Leach <[email protected]>; pgsql-hackers
Hi Brandur,
Couple of typo corrections required in patch:
s/converstion/conversion
s/go the heap/go to the heap
The performance results you shared are for he Index Creation operation.
Are there similar results for the sorting using ORDER BY queries too? Just
curious.
Regards,
Neha
^ permalink raw reply [nested|flat] 134+ messages in thread
* Re: [PATCH] SortSupport for macaddr type
@ 2017-03-14 10:25 Heikki Linnakangas <[email protected]>
parent: Neha Khatri <[email protected]>
0 siblings, 1 reply; 134+ messages in thread
From: Heikki Linnakangas @ 2017-03-14 10:25 UTC (permalink / raw)
To: Brandur Leach <[email protected]>; +Cc: Neha Khatri <[email protected]>; Julien Rouhaud <[email protected]>; pgsql-hackers
Looks straightforward at a quick read-through. I have just a couple of
questions. How much of the performance gain comes from avoiding the
FunctionCallInvoke overhead, by simply having SortSupport with a
comparison function, and how much comes from the "abbreviation"?
Also, is it worth the cycles and code to have the hyperloglog estimator,
and aborting the abbreviation if there are only a few distinct values.
Or put another way, how much does the abbreviation slow things down in
the worst case?
- Heikki
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^ permalink raw reply [nested|flat] 134+ messages in thread
* Re: [PATCH] SortSupport for macaddr type
@ 2017-03-18 21:54 Peter Geoghegan <[email protected]>
parent: Heikki Linnakangas <[email protected]>
0 siblings, 1 reply; 134+ messages in thread
From: Peter Geoghegan @ 2017-03-18 21:54 UTC (permalink / raw)
To: Heikki Linnakangas <[email protected]>; +Cc: Brandur Leach <[email protected]>; Neha Khatri <[email protected]>; Julien Rouhaud <[email protected]>; pgsql-hackers
On Tue, Mar 14, 2017 at 3:25 AM, Heikki Linnakangas <[email protected]> wrote:
> Looks straightforward at a quick read-through. I have just a couple of
> questions. How much of the performance gain comes from avoiding the
> FunctionCallInvoke overhead, by simply having SortSupport with a comparison
> function, and how much comes from the "abbreviation"?
I assume it's very similar to the existing performance characteristics
that UUID SortSupport has.
> Also, is it worth the cycles and code to have the hyperloglog estimator, and
> aborting the abbreviation if there are only a few distinct values. Or put
> another way, how much does the abbreviation slow things down in the worst
> case?
Postgres doesn't support passing 6 byte types by-value due to a lack
of support from macros in places like postgres.h. There is a
GET_4_BYTES(), and a GET_8_BYTES(), but no GET_6_BYTES(). It doesn't
really seem worth adding those, just like it didn't seem worth it back
when I pointed out that a TID sort is very slow in the context of
CREATE INDEX CONCURRENTLY. (We ended up coming up with an ad-hoc int8
encoding scheme there, which allowed us to use the int8 default
opclass rather than the TID default opclass, you'll recall.)
It's a bit odd that macaddr abbreviated keys are actually always
smaller (not including padding) than sizeof(Datum) on 64-bit machines,
but this guarantees that abbreviated comparisons will reliably
indicate what an authoritative comparison would indicate, since of
course all relevant information is right there in the abbreviated key.
This will be the only time where that's generally true with
abbreviated keys for any type. This seems fine to me, especially
because it lets us compare macaddr using simple 3-way unsigned int
comparisons, which isn't otherwise the case.
I doubt that you'll ever see a real need to abort abbreviation.
Arguably it shouldn't be considered, but maybe it's worth being
consistent. It might matter on 32-bit platforms, where there is only a
single NIC-specific byte to differentiate MAC addresses, but even that
seems like a stretch. With a type like macaddr, where there is no
major cost like strxfrm() to worry about when abbreviating, the only
cost of abbreviating is that tie-breakers will have an extra
index_getattr() or similar. If there was no abbreviation, or if it
aborted, then the index_getattr() can happen once per SortTuple,
up-front.
Nitpick: the patch should probably not refer to 32-bit or 64-bit
systems. Rather, it should refer to Datum size only.
--
Peter Geoghegan
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^ permalink raw reply [nested|flat] 134+ messages in thread
* Re: [PATCH] SortSupport for macaddr type
@ 2017-03-18 22:22 Peter Geoghegan <[email protected]>
parent: Peter Geoghegan <[email protected]>
0 siblings, 1 reply; 134+ messages in thread
From: Peter Geoghegan @ 2017-03-18 22:22 UTC (permalink / raw)
To: Heikki Linnakangas <[email protected]>; +Cc: Brandur Leach <[email protected]>; Neha Khatri <[email protected]>; Julien Rouhaud <[email protected]>; pgsql-hackers
On Sat, Mar 18, 2017 at 2:54 PM, Peter Geoghegan <[email protected]> wrote:
> This seems fine to me, especially
> because it lets us compare macaddr using simple 3-way unsigned int
> comparisons, which isn't otherwise the case.
Out of idle curiosity, I decided to generate disassembly of both
macaddr_cmp_internal(), and the patch's abbreviated comparator. The
former consists of 49 x86-64 instructions at -02 on my machine,
totaling 135 bytes of object code. The latter consists of only 10
instructions, or 24 bytes of object code.
--
Peter Geoghegan
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^ permalink raw reply [nested|flat] 134+ messages in thread
* Re: [PATCH] SortSupport for macaddr type
@ 2017-03-19 15:40 Greg Stark <[email protected]>
parent: Peter Geoghegan <[email protected]>
0 siblings, 1 reply; 134+ messages in thread
From: Greg Stark @ 2017-03-19 15:40 UTC (permalink / raw)
To: Peter Geoghegan <[email protected]>; +Cc: Heikki Linnakangas <[email protected]>; Brandur Leach <[email protected]>; Neha Khatri <[email protected]>; Julien Rouhaud <[email protected]>; pgsql-hackers
On 18 March 2017 at 22:22, Peter Geoghegan <[email protected]> wrote:
>
> Out of idle curiosity, I decided to generate disassembly of both
> macaddr_cmp_internal(), and the patch's abbreviated comparator. The
> former consists of 49 x86-64 instructions at -02 on my machine,
> totaling 135 bytes of object code. The latter consists of only 10
> instructions, or 24 bytes of object code.
I wonder if there's something that could be optimized out of the
normal cmp function but we're defeating some compiler optimizations
with all our casts and aliasing.
--
greg
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^ permalink raw reply [nested|flat] 134+ messages in thread
* Re: [PATCH] SortSupport for macaddr type
@ 2017-03-19 17:36 Peter Geoghegan <[email protected]>
parent: Greg Stark <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Peter Geoghegan @ 2017-03-19 17:36 UTC (permalink / raw)
To: Greg Stark <[email protected]>; +Cc: Heikki Linnakangas <[email protected]>; Brandur Leach <[email protected]>; Neha Khatri <[email protected]>; Julien Rouhaud <[email protected]>; pgsql-hackers
On Sun, Mar 19, 2017 at 8:40 AM, Greg Stark <[email protected]> wrote:
>> Out of idle curiosity, I decided to generate disassembly of both
>> macaddr_cmp_internal(), and the patch's abbreviated comparator. The
>> former consists of 49 x86-64 instructions at -02 on my machine,
>> totaling 135 bytes of object code. The latter consists of only 10
>> instructions, or 24 bytes of object code.
>
> I wonder if there's something that could be optimized out of the
> normal cmp function but we're defeating some compiler optimizations
> with all our casts and aliasing.
There was one shl instruction for every left shift (hibits() or
lowbits() call) that appears in macaddr_cmp_internal(). I suppose that
it's possible that that could have been better optimized on a
big-endian machine, where abbreviated keys do not need to be
byteswaped to make the abbreviated comparator work. Perhaps the
compiler could have recognized that macaddr is a struct that consists
of 6 unsigned bytes as digits.
One thing that I've noticed makes a relatively big difference to
instruction count in comparators is varlena overhead, which does come
up here, since macaddr is a type that doesn't have a varlena header
(it was recently suggested by Tom that this is a mistake on practical
grounds, though). I've informally considered the possibility of
providing alternative versions of comparators that do not detoast or
work with anything other than 1-byte header varlenas, because
tuplesort has detected that that happens to be generally safe. I doubt
that I'll ever get around to posting a patch to do that, since the
cost savings are probably still marginal. I could probably find
something better to work on.
--
Peter Geoghegan
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^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v7 3/9] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 441445927e..da8a460722 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index b7f8e12aea..18dd4ff1eb 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 134f6862da..593a4140df 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--JYK4vJDZwFMowpUq
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v7-0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v8 3/9] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 441445927e..da8a460722 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 64094e7175..18d8743715 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1162,7 +1162,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 134f6862da..593a4140df 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--P+33d92oIH25kiaB
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v8-0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/12] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 5b657ec724..8db3727502 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--45Z9DzgjV8m4Oswq
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--jozmn01XJZjDjM3N
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/12] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 5b657ec724..8db3727502 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--45Z9DzgjV8m4Oswq
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 6/6] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 56 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 60 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index bb1f106946..f0ba9c33ed 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -204,7 +204,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool topXidLogged; /* for a subxact: is top-level XID logged? */
@@ -523,12 +523,16 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
/*
@@ -582,6 +586,35 @@ MarkSubxactTopXidLogged(void)
CurrentTransactionState->topXidLogged = true;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
+
/*
* GetStableLatestTransactionId
*
@@ -669,14 +702,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -746,6 +779,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -760,11 +794,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2049,7 +2085,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 198e6906ee..7c7bea768c 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -915,7 +915,7 @@ XLogInsertRecord(XLogRecData *rdata,
END_CRIT_SECTION();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
/*
* Mark top transaction id is logged (if needed) so that we should not try
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index 60e57876de..47bae59898 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 17a6fa4abd..33d03e1913 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.1
--pAwQNkOnpTn9IO2O--
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v9 3/9] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 441445927e..da8a460722 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 1ccc51575a..f7909aa1d7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1162,7 +1162,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 134f6862da..593a4140df 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--neYutvxvOLaeuPCA
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="v9-0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH v1 2/2] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4e6a3df6b8..85b1c21ee0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -1996,7 +2031,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 377afb8732..1a503c1447 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1159,7 +1159,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index f49a57b35e..536a5e653b 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.27.0
----Next_Part(Mon_Mar__8_17_32_42_2021_572)----
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 2/8] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index e04250f4e9..e3128564e1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1161,7 +1161,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--f0KYrhQ4vYSV2aJu
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0003-Allow-alternate-compression-methods-for-wal_compress.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 04192b7add..0183589b4d 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1171,7 +1171,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--0qVF/w3MHQqLSynd
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* [PATCH 03/10] Make sure published XIDs are persistent
@ 2021-03-08 06:43 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Kyotaro Horiguchi @ 2021-03-08 06:43 UTC (permalink / raw)
pg_xact_status() premises that XIDs obtained by
pg_current_xact_id(_if_assigned)() are persistent beyond a crash. But
XIDs are not guaranteed to go beyond WAL buffers before commit and
thus XIDs may vanish if server crashes before commit. This patch
guarantees the XID shown by the functions to be flushed out to disk.
Copied from: https://www.postgresql.org/message-id/20210308.173242.463790587797836129.horikyota.ntt%40gmail.com
---
src/backend/access/transam/xact.c | 55 +++++++++++++++++++++++++------
src/backend/access/transam/xlog.c | 2 +-
src/backend/utils/adt/xid8funcs.c | 12 ++++++-
src/include/access/xact.h | 3 +-
4 files changed, 59 insertions(+), 13 deletions(-)
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6395a9b240..38e978d238 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -201,7 +201,7 @@ typedef struct TransactionStateData
int prevSecContext; /* previous SecurityRestrictionContext */
bool prevXactReadOnly; /* entry-time xact r/o state */
bool startedInRecovery; /* did we start in recovery? */
- bool didLogXid; /* has xid been included in WAL record? */
+ XLogRecPtr minLSN; /* LSN needed to reach to record the xid */
int parallelModeLevel; /* Enter/ExitParallelMode counter */
bool chain; /* start a new block after this one */
bool assigned; /* assigned to top-level XID */
@@ -520,14 +520,46 @@ GetCurrentFullTransactionIdIfAny(void)
* MarkCurrentTransactionIdLoggedIfAny
*
* Remember that the current xid - if it is assigned - now has been wal logged.
+ *
+ * upto is the LSN up to which we need to flush WAL to ensure the current xid
+ * to be persistent. See EnsureCurrentTransactionIdLogged().
*/
void
-MarkCurrentTransactionIdLoggedIfAny(void)
+MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto)
{
- if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId))
- CurrentTransactionState->didLogXid = true;
+ if (FullTransactionIdIsValid(CurrentTransactionState->fullTransactionId) &&
+ XLogRecPtrIsInvalid(CurrentTransactionState->minLSN))
+ CurrentTransactionState->minLSN = upto;
}
+/*
+ * EnsureCurrentTransactionIdLogged
+ *
+ * Make sure that the current top XID is WAL-logged.
+ */
+void
+EnsureTopTransactionIdLogged(void)
+{
+ /*
+ * We need at least one WAL record for the current top transaction to be
+ * flushed out. Write one if we don't have one yet.
+ */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ {
+ xl_xact_assignment xlrec;
+
+ xlrec.xtop = XidFromFullTransactionId(XactTopFullTransactionId);
+ Assert(TransactionIdIsValid(xlrec.xtop));
+ xlrec.nsubxacts = 0;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, MinSizeOfXactAssignment);
+ TopTransactionStateData.minLSN =
+ XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ }
+
+ XLogFlush(TopTransactionStateData.minLSN);
+}
/*
* GetStableLatestTransactionId
@@ -616,14 +648,14 @@ AssignTransactionId(TransactionState s)
* When wal_level=logical, guarantee that a subtransaction's xid can only
* be seen in the WAL stream if its toplevel xid has been logged before.
* If necessary we log an xact_assignment record with fewer than
- * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if didLogXid isn't set
+ * PGPROC_MAX_CACHED_SUBXIDS. Note that it is fine if minLSN isn't set
* for a transaction even though it appears in a WAL record, we just might
* superfluously log something. That can happen when an xid is included
* somewhere inside a wal record, but not in XLogRecord->xl_xid, like in
* xl_standby_locks.
*/
if (isSubXact && XLogLogicalInfoActive() &&
- !TopTransactionStateData.didLogXid)
+ XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
log_unknown_top = true;
/*
@@ -693,6 +725,7 @@ AssignTransactionId(TransactionState s)
log_unknown_top)
{
xl_xact_assignment xlrec;
+ XLogRecPtr endptr;
/*
* xtop is always set by now because we recurse up transaction
@@ -707,11 +740,13 @@ AssignTransactionId(TransactionState s)
XLogRegisterData((char *) unreportedXids,
nUnreportedXids * sizeof(TransactionId));
- (void) XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
+ endptr = XLogInsert(RM_XACT_ID, XLOG_XACT_ASSIGNMENT);
nUnreportedXids = 0;
- /* mark top, not current xact as having been logged */
- TopTransactionStateData.didLogXid = true;
+
+ /* set minLSN of top, not of current xact if not yet */
+ if (XLogRecPtrIsInvalid(TopTransactionStateData.minLSN))
+ TopTransactionStateData.minLSN = endptr;
}
}
}
@@ -2022,7 +2057,7 @@ StartTransaction(void)
* initialize reported xid accounting
*/
nUnreportedXids = 0;
- s->didLogXid = false;
+ s->minLSN = InvalidXLogRecPtr;
/*
* must initialize resource-management stuff first
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15da91a8dd..6eb46ea8a7 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1172,7 +1172,7 @@ XLogInsertRecord(XLogRecData *rdata,
*/
WALInsertLockRelease();
- MarkCurrentTransactionIdLoggedIfAny();
+ MarkCurrentTransactionIdLoggedIfAny(EndPos);
END_CRIT_SECTION();
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index cc2b4ac797..992482f8c8 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -357,6 +357,8 @@ bad_format:
Datum
pg_current_xact_id(PG_FUNCTION_ARGS)
{
+ FullTransactionId xid;
+
/*
* Must prevent during recovery because if an xid is not assigned we try
* to assign one, which would fail. Programs already rely on this function
@@ -365,7 +367,12 @@ pg_current_xact_id(PG_FUNCTION_ARGS)
*/
PreventCommandDuringRecovery("pg_current_xact_id()");
- PG_RETURN_FULLTRANSACTIONID(GetTopFullTransactionId());
+ xid = GetTopFullTransactionId();
+
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
+ PG_RETURN_FULLTRANSACTIONID(xid);
}
/*
@@ -380,6 +387,9 @@ pg_current_xact_id_if_assigned(PG_FUNCTION_ARGS)
if (!FullTransactionIdIsValid(topfxid))
PG_RETURN_NULL();
+ /* the XID is going to be published, make sure it is psersistent */
+ EnsureTopTransactionIdLogged();
+
PG_RETURN_FULLTRANSACTIONID(topfxid);
}
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 34cfaf542c..a61e4d6da5 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -386,7 +386,8 @@ extern FullTransactionId GetTopFullTransactionId(void);
extern FullTransactionId GetTopFullTransactionIdIfAny(void);
extern FullTransactionId GetCurrentFullTransactionId(void);
extern FullTransactionId GetCurrentFullTransactionIdIfAny(void);
-extern void MarkCurrentTransactionIdLoggedIfAny(void);
+extern void MarkCurrentTransactionIdLoggedIfAny(XLogRecPtr upto);
+extern void EnsureTopTransactionIdLogged(void);
extern bool SubTransactionIsActive(SubTransactionId subxid);
extern CommandId GetCurrentCommandId(bool used);
extern void SetParallelStartTimestamps(TimestampTz xact_ts, TimestampTz stmt_ts);
--
2.17.0
--XsQoSWH+UP9D9v3l
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
filename="0004-wal_compression_method-default-to-zlib.patch"
^ permalink raw reply [nested|flat] 134+ messages in thread
* max_standby_streaming_delay setting not cancelling query on replica
@ 2023-11-01 16:58 Ben Snaidero <[email protected]>
0 siblings, 0 replies; 134+ messages in thread
From: Ben Snaidero @ 2023-11-01 16:58 UTC (permalink / raw)
To: [email protected]
Hi,
We are running a postgres streaming replica with
max_standby_streaming_delay set to 900 seconds (15min). We encountered an
issue in our environment where we had a long running query that was running
against the replica for just over 4 hours causing 4 hours of replication
lag. Looking at pg_stat_activity for this query it was stuck in
Client:ClientWrite wait state for pretty much all of this time (it ran for
less than 1 minute before going into ClientWrite wait state. We capture
pg_stat_activity every minute and only first capture shows a DataFileRead
wait and there was only 1 other capture during the 4 hours where it was
active with no wait event). From what we could tell the client process
tried to send cancellation and disconnected (our client application uses
npgsql) so there was no process to consume these results and after manually
cancelling the query the replication lag came back down so this query was
definitely the cause of the lag.
Question: Why did the max_standby_streaming_delay setting not cancel this
query?
I looked at the code in standby.c and if there are conflicting locks it
should be cancelled. Unfortunately at the time this issue occurred we
weren't collecting pg_locks to see what locks are being held but given the
state the query was in would it have released the ACCESS SHARE lock it
acquired while executing the query given it just has to send data to the
client now? I would think if it still held this lock then the query would
be cancelled. If it didn't hold it anymore then maybe that is why
max_standby_streaming_delay setting didn't cause it to be cancelled. Any
other ideas?
Thanks,
Ben
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2017-03-02 22:39 Re: [PATCH] SortSupport for macaddr type Julien Rouhaud <[email protected]>
2017-03-03 02:27 ` Neha Khatri <[email protected]>
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2017-03-18 21:54 ` Peter Geoghegan <[email protected]>
2017-03-18 22:22 ` Peter Geoghegan <[email protected]>
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2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v9 3/9] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/12] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v7 3/9] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
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2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH v1 2/2] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/12] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 03/10] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2021-03-08 06:43 [PATCH 2/8] Make sure published XIDs are persistent Kyotaro Horiguchi <[email protected]>
2023-11-01 16:58 max_standby_streaming_delay setting not cancelling query on replica Ben Snaidero <[email protected]>
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