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* [PATCH v47 3/7] Make archiver process an auxiliary process
@ 2020-03-13 07:59 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 5+ messages in thread
From: Kyotaro Horiguchi @ 2020-03-13 07:59 UTC (permalink / raw)
This is a preliminary patch for shared-memory based stats collector.
Archiver process must be a auxiliary process since it uses shared
memory after stats data was moved into shared-memory. Make the process
an auxiliary process in order to make it work.
---
src/backend/access/transam/xlogarchive.c | 6 +-
src/backend/bootstrap/bootstrap.c | 22 ++--
src/backend/postmaster/pgarch.c | 130 +++--------------------
src/backend/postmaster/postmaster.c | 50 +++++----
src/backend/storage/lmgr/proc.c | 1 +
src/include/access/xlog.h | 3 +
src/include/access/xlogarchive.h | 1 +
src/include/miscadmin.h | 2 +
src/include/postmaster/pgarch.h | 4 +-
src/include/storage/pmsignal.h | 1 -
src/include/storage/proc.h | 3 +
11 files changed, 69 insertions(+), 154 deletions(-)
diff --git a/src/backend/access/transam/xlogarchive.c b/src/backend/access/transam/xlogarchive.c
index 1c5a4f8b5a..d01859bde5 100644
--- a/src/backend/access/transam/xlogarchive.c
+++ b/src/backend/access/transam/xlogarchive.c
@@ -29,7 +29,9 @@
#include "storage/fd.h"
#include "storage/ipc.h"
#include "storage/lwlock.h"
+#include "storage/latch.h"
#include "storage/pmsignal.h"
+#include "storage/proc.h"
/*
* Attempt to retrieve the specified file from off-line archival storage.
@@ -490,8 +492,8 @@ XLogArchiveNotify(const char *xlog)
}
/* Notify archiver that it's got something to do */
- if (IsUnderPostmaster)
- SendPostmasterSignal(PMSIGNAL_WAKEN_ARCHIVER);
+ if (IsUnderPostmaster && ProcGlobal->archiverLatch)
+ SetLatch(ProcGlobal->archiverLatch);
}
/*
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index 6f615e6622..41da0c5059 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -317,6 +317,9 @@ AuxiliaryProcessMain(int argc, char *argv[])
case StartupProcess:
MyBackendType = B_STARTUP;
break;
+ case ArchiverProcess:
+ MyBackendType = B_ARCHIVER;
+ break;
case BgWriterProcess:
MyBackendType = B_BG_WRITER;
break;
@@ -437,30 +440,29 @@ AuxiliaryProcessMain(int argc, char *argv[])
proc_exit(1); /* should never return */
case StartupProcess:
- /* don't set signals, startup process has its own agenda */
StartupProcessMain();
- proc_exit(1); /* should never return */
+ proc_exit(1);
+
+ case ArchiverProcess:
+ PgArchiverMain();
+ proc_exit(1);
case BgWriterProcess:
- /* don't set signals, bgwriter has its own agenda */
BackgroundWriterMain();
- proc_exit(1); /* should never return */
+ proc_exit(1);
case CheckpointerProcess:
- /* don't set signals, checkpointer has its own agenda */
CheckpointerMain();
- proc_exit(1); /* should never return */
+ proc_exit(1);
case WalWriterProcess:
- /* don't set signals, walwriter has its own agenda */
InitXLOGAccess();
WalWriterMain();
- proc_exit(1); /* should never return */
+ proc_exit(1);
case WalReceiverProcess:
- /* don't set signals, walreceiver has its own agenda */
WalReceiverMain();
- proc_exit(1); /* should never return */
+ proc_exit(1);
default:
elog(PANIC, "unrecognized process type: %d", (int) MyAuxProcType);
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index edec311f12..9a2e21bf86 100644
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -48,6 +48,7 @@
#include "storage/latch.h"
#include "storage/pg_shmem.h"
#include "storage/pmsignal.h"
+#include "storage/procsignal.h"
#include "utils/guc.h"
#include "utils/ps_status.h"
@@ -78,13 +79,11 @@
* Local data
* ----------
*/
-static time_t last_pgarch_start_time;
static time_t last_sigterm_time = 0;
/*
* Flags set by interrupt handlers for later service in the main loop.
*/
-static volatile sig_atomic_t wakened = false;
static volatile sig_atomic_t ready_to_stop = false;
/* ----------
@@ -95,8 +94,6 @@ static volatile sig_atomic_t ready_to_stop = false;
static pid_t pgarch_forkexec(void);
#endif
-NON_EXEC_STATIC void PgArchiverMain(int argc, char *argv[]) pg_attribute_noreturn();
-static void pgarch_waken(SIGNAL_ARGS);
static void pgarch_waken_stop(SIGNAL_ARGS);
static void pgarch_MainLoop(void);
static void pgarch_ArchiverCopyLoop(void);
@@ -110,75 +107,6 @@ static void pgarch_archiveDone(char *xlog);
* ------------------------------------------------------------
*/
-/*
- * pgarch_start
- *
- * Called from postmaster at startup or after an existing archiver
- * died. Attempt to fire up a fresh archiver process.
- *
- * Returns PID of child process, or 0 if fail.
- *
- * Note: if fail, we will be called again from the postmaster main loop.
- */
-int
-pgarch_start(void)
-{
- time_t curtime;
- pid_t pgArchPid;
-
- /*
- * Do nothing if no archiver needed
- */
- if (!XLogArchivingActive())
- return 0;
-
- /*
- * Do nothing if too soon since last archiver start. This is a safety
- * valve to protect against continuous respawn attempts if the archiver is
- * dying immediately at launch. Note that since we will be re-called from
- * the postmaster main loop, we will get another chance later.
- */
- curtime = time(NULL);
- if ((unsigned int) (curtime - last_pgarch_start_time) <
- (unsigned int) PGARCH_RESTART_INTERVAL)
- return 0;
- last_pgarch_start_time = curtime;
-
-#ifdef EXEC_BACKEND
- switch ((pgArchPid = pgarch_forkexec()))
-#else
- switch ((pgArchPid = fork_process()))
-#endif
- {
- case -1:
- ereport(LOG,
- (errmsg("could not fork archiver: %m")));
- return 0;
-
-#ifndef EXEC_BACKEND
- case 0:
- /* in postmaster child ... */
- InitPostmasterChild();
-
- /* Close the postmaster's sockets */
- ClosePostmasterPorts(false);
-
- /* Drop our connection to postmaster's shared memory, as well */
- dsm_detach_all();
- PGSharedMemoryDetach();
-
- PgArchiverMain(0, NULL);
- break;
-#endif
-
- default:
- return (int) pgArchPid;
- }
-
- /* shouldn't get here */
- return 0;
-}
-
/* ------------------------------------------------------------
* Local functions called by archiver follow
* ------------------------------------------------------------
@@ -212,14 +140,9 @@ pgarch_forkexec(void)
#endif /* EXEC_BACKEND */
-/*
- * PgArchiverMain
- *
- * The argc/argv parameters are valid only in EXEC_BACKEND case. However,
- * since we don't use 'em, it hardly matters...
- */
-NON_EXEC_STATIC void
-PgArchiverMain(int argc, char *argv[])
+/* Main entry point for archiver process */
+void
+PgArchiverMain(void)
{
/*
* Ignore all signals usually bound to some action in the postmaster,
@@ -231,33 +154,26 @@ PgArchiverMain(int argc, char *argv[])
/* SIGQUIT handler was already set up by InitPostmasterChild */
pqsignal(SIGALRM, SIG_IGN);
pqsignal(SIGPIPE, SIG_IGN);
- pqsignal(SIGUSR1, pgarch_waken);
+ pqsignal(SIGUSR1, procsignal_sigusr1_handler);
pqsignal(SIGUSR2, pgarch_waken_stop);
+
/* Reset some signals that are accepted by postmaster but not here */
pqsignal(SIGCHLD, SIG_DFL);
+
+ /* Unblock signals (they were blocked when the postmaster forked us) */
PG_SETMASK(&UnBlockSig);
- MyBackendType = B_ARCHIVER;
- init_ps_display(NULL);
+ /*
+ * Advertise our latch that backends can use to wake us up while we're
+ * sleeping.
+ */
+ ProcGlobal->archiverLatch = &MyProc->procLatch;
pgarch_MainLoop();
exit(0);
}
-/* SIGUSR1 signal handler for archiver process */
-static void
-pgarch_waken(SIGNAL_ARGS)
-{
- int save_errno = errno;
-
- /* set flag that there is work to be done */
- wakened = true;
- SetLatch(MyLatch);
-
- errno = save_errno;
-}
-
/* SIGUSR2 signal handler for archiver process */
static void
pgarch_waken_stop(SIGNAL_ARGS)
@@ -282,14 +198,6 @@ pgarch_MainLoop(void)
pg_time_t last_copy_time = 0;
bool time_to_stop;
- /*
- * We run the copy loop immediately upon entry, in case there are
- * unarchived files left over from a previous database run (or maybe the
- * archiver died unexpectedly). After that we wait for a signal or
- * timeout before doing more.
- */
- wakened = true;
-
/*
* There shouldn't be anything for the archiver to do except to wait for a
* signal ... however, the archiver exists to protect our data, so she
@@ -328,12 +236,8 @@ pgarch_MainLoop(void)
}
/* Do what we're here for */
- if (wakened || time_to_stop)
- {
- wakened = false;
- pgarch_ArchiverCopyLoop();
- last_copy_time = time(NULL);
- }
+ pgarch_ArchiverCopyLoop();
+ last_copy_time = time(NULL);
/*
* Sleep until a signal is received, or until a poll is forced by
@@ -354,13 +258,9 @@ pgarch_MainLoop(void)
WL_LATCH_SET | WL_TIMEOUT | WL_POSTMASTER_DEATH,
timeout * 1000L,
WAIT_EVENT_ARCHIVER_MAIN);
- if (rc & WL_TIMEOUT)
- wakened = true;
if (rc & WL_POSTMASTER_DEATH)
time_to_stop = true;
}
- else
- wakened = true;
}
/*
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 7de27ee4e0..af91c313e2 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -548,6 +548,7 @@ static void ShmemBackendArrayRemove(Backend *bn);
#endif /* EXEC_BACKEND */
#define StartupDataBase() StartChildProcess(StartupProcess)
+#define StartArchiver() StartChildProcess(ArchiverProcess)
#define StartBackgroundWriter() StartChildProcess(BgWriterProcess)
#define StartCheckpointer() StartChildProcess(CheckpointerProcess)
#define StartWalWriter() StartChildProcess(WalWriterProcess)
@@ -1788,7 +1789,7 @@ ServerLoop(void)
/* If we have lost the archiver, try to start a new one. */
if (PgArchPID == 0 && PgArchStartupAllowed())
- PgArchPID = pgarch_start();
+ PgArchPID = StartArchiver();
/* If we need to signal the autovacuum launcher, do so now */
if (avlauncher_needs_signal)
@@ -3027,7 +3028,7 @@ reaper(SIGNAL_ARGS)
if (!IsBinaryUpgrade && AutoVacuumingActive() && AutoVacPID == 0)
AutoVacPID = StartAutoVacLauncher();
if (PgArchStartupAllowed() && PgArchPID == 0)
- PgArchPID = pgarch_start();
+ PgArchPID = StartArchiver();
if (PgStatPID == 0)
PgStatPID = pgstat_start();
@@ -3162,20 +3163,16 @@ reaper(SIGNAL_ARGS)
}
/*
- * Was it the archiver? If so, just try to start a new one; no need
- * to force reset of the rest of the system. (If fail, we'll try
- * again in future cycles of the main loop.). Unless we were waiting
- * for it to shut down; don't restart it in that case, and
- * PostmasterStateMachine() will advance to the next shutdown step.
+ * Was it the archiver? Normal exit can be ignored; we'll start a new
+ * one at the next iteration of the postmaster's main loop, if
+ * necessary. Any other exit condition is treated as a crash.
*/
if (pid == PgArchPID)
{
PgArchPID = 0;
if (!EXIT_STATUS_0(exitstatus))
- LogChildExit(LOG, _("archiver process"),
- pid, exitstatus);
- if (PgArchStartupAllowed())
- PgArchPID = pgarch_start();
+ HandleChildCrash(pid, exitstatus,
+ _("archiver process"));
continue;
}
@@ -3423,7 +3420,7 @@ CleanupBackend(int pid,
/*
* HandleChildCrash -- cleanup after failed backend, bgwriter, checkpointer,
- * walwriter, autovacuum, or background worker.
+ * walwriter, autovacuum, archiver or background worker.
*
* The objectives here are to clean up our local state about the child
* process, and to signal all other remaining children to quickdie.
@@ -3629,6 +3626,18 @@ HandleChildCrash(int pid, int exitstatus, const char *procname)
signal_child(AutoVacPID, (SendStop ? SIGSTOP : SIGQUIT));
}
+ /* Take care of the archiver too */
+ if (pid == PgArchPID)
+ PgArchPID = 0;
+ else if (PgArchPID != 0 && take_action)
+ {
+ ereport(DEBUG2,
+ (errmsg_internal("sending %s to process %d",
+ (SendStop ? "SIGSTOP" : "SIGQUIT"),
+ (int) PgArchPID)));
+ signal_child(PgArchPID, (SendStop ? SIGSTOP : SIGQUIT));
+ }
+
/*
* Force a power-cycle of the pgarch process too. (This isn't absolutely
* necessary, but it seems like a good idea for robustness, and it
@@ -3932,6 +3941,7 @@ PostmasterStateMachine(void)
Assert(CheckpointerPID == 0);
Assert(WalWriterPID == 0);
Assert(AutoVacPID == 0);
+ Assert(PgArchPID == 0);
/* syslogger is not considered here */
pmState = PM_NO_CHILDREN;
}
@@ -5160,7 +5170,7 @@ sigusr1_handler(SIGNAL_ARGS)
*/
Assert(PgArchPID == 0);
if (XLogArchivingAlways())
- PgArchPID = pgarch_start();
+ PgArchPID = StartArchiver();
/*
* If we aren't planning to enter hot standby mode later, treat
@@ -5214,16 +5224,6 @@ sigusr1_handler(SIGNAL_ARGS)
if (StartWorkerNeeded || HaveCrashedWorker)
maybe_start_bgworkers();
- if (CheckPostmasterSignal(PMSIGNAL_WAKEN_ARCHIVER) &&
- PgArchPID != 0)
- {
- /*
- * Send SIGUSR1 to archiver process, to wake it up and begin archiving
- * next WAL file.
- */
- signal_child(PgArchPID, SIGUSR1);
- }
-
/* Tell syslogger to rotate logfile if requested */
if (SysLoggerPID != 0)
{
@@ -5465,6 +5465,10 @@ StartChildProcess(AuxProcType type)
ereport(LOG,
(errmsg("could not fork startup process: %m")));
break;
+ case ArchiverProcess:
+ ereport(LOG,
+ (errmsg("could not fork archiver process: %m")));
+ break;
case BgWriterProcess:
ereport(LOG,
(errmsg("could not fork background writer process: %m")));
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index c87ffc6549..a1e51c5b99 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -182,6 +182,7 @@ InitProcGlobal(void)
ProcGlobal->startupBufferPinWaitBufId = -1;
ProcGlobal->walwriterLatch = NULL;
ProcGlobal->checkpointerLatch = NULL;
+ ProcGlobal->archiverLatch = NULL;
pg_atomic_init_u32(&ProcGlobal->procArrayGroupFirst, INVALID_PGPROCNO);
pg_atomic_init_u32(&ProcGlobal->clogGroupFirst, INVALID_PGPROCNO);
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index 75ec1073bd..551f518cc2 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -339,6 +339,9 @@ extern XLogRecPtr GetRedoRecPtr(void);
extern XLogRecPtr GetInsertRecPtr(void);
extern XLogRecPtr GetFlushRecPtr(void);
extern XLogRecPtr GetLastImportantRecPtr(void);
+extern void XLogArchiveWakeupStart(void);
+extern void XLogArchiveWakeupEnd(void);
+extern void XLogArchiveWakeup(void);
extern void RemovePromoteSignalFiles(void);
extern bool PromoteIsTriggered(void);
diff --git a/src/include/access/xlogarchive.h b/src/include/access/xlogarchive.h
index 3edd1a976c..1a59181cf9 100644
--- a/src/include/access/xlogarchive.h
+++ b/src/include/access/xlogarchive.h
@@ -25,6 +25,7 @@ extern void ExecuteRecoveryCommand(const char *command, const char *commandName,
extern void KeepFileRestoredFromArchive(const char *path, const char *xlogfname);
extern void XLogArchiveNotify(const char *xlog);
extern void XLogArchiveNotifySeg(XLogSegNo segno);
+extern void XLogArchiveWakeup(void);
extern void XLogArchiveForceDone(const char *xlog);
extern bool XLogArchiveCheckDone(const char *xlog);
extern bool XLogArchiveIsBusy(const char *xlog);
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index 1bdc97e308..adb9f819bb 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -419,6 +419,7 @@ typedef enum
BootstrapProcess,
StartupProcess,
BgWriterProcess,
+ ArchiverProcess,
CheckpointerProcess,
WalWriterProcess,
WalReceiverProcess,
@@ -431,6 +432,7 @@ extern AuxProcType MyAuxProcType;
#define AmBootstrapProcess() (MyAuxProcType == BootstrapProcess)
#define AmStartupProcess() (MyAuxProcType == StartupProcess)
#define AmBackgroundWriterProcess() (MyAuxProcType == BgWriterProcess)
+#define AmArchiverProcess() (MyAuxProcType == ArchiverProcess)
#define AmCheckpointerProcess() (MyAuxProcType == CheckpointerProcess)
#define AmWalWriterProcess() (MyAuxProcType == WalWriterProcess)
#define AmWalReceiverProcess() (MyAuxProcType == WalReceiverProcess)
diff --git a/src/include/postmaster/pgarch.h b/src/include/postmaster/pgarch.h
index d102a21ab7..385b002dfe 100644
--- a/src/include/postmaster/pgarch.h
+++ b/src/include/postmaster/pgarch.h
@@ -32,8 +32,6 @@
*/
extern int pgarch_start(void);
-#ifdef EXEC_BACKEND
-extern void PgArchiverMain(int argc, char *argv[]) pg_attribute_noreturn();
-#endif
+extern void PgArchiverMain(void) pg_attribute_noreturn();
#endif /* _PGARCH_H */
diff --git a/src/include/storage/pmsignal.h b/src/include/storage/pmsignal.h
index dbbed18f61..8ed4d87ae6 100644
--- a/src/include/storage/pmsignal.h
+++ b/src/include/storage/pmsignal.h
@@ -34,7 +34,6 @@ typedef enum
{
PMSIGNAL_RECOVERY_STARTED, /* recovery has started */
PMSIGNAL_BEGIN_HOT_STANDBY, /* begin Hot Standby */
- PMSIGNAL_WAKEN_ARCHIVER, /* send a NOTIFY signal to xlog archiver */
PMSIGNAL_ROTATE_LOGFILE, /* send SIGUSR1 to syslogger to rotate logfile */
PMSIGNAL_START_AUTOVAC_LAUNCHER, /* start an autovacuum launcher */
PMSIGNAL_START_AUTOVAC_WORKER, /* start an autovacuum worker */
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h
index 683ab64f76..6cdaf3753d 100644
--- a/src/include/storage/proc.h
+++ b/src/include/storage/proc.h
@@ -355,6 +355,9 @@ typedef struct PROC_HDR
int startupProcPid;
/* Buffer id of the buffer that Startup process waits for pin on, or -1 */
int startupBufferPinWaitBufId;
+ /* Archiver process's latch */
+ Latch *archiverLatch;
+ /* Current shared estimate of appropriate spins_per_delay value */
} PROC_HDR;
extern PGDLLIMPORT PROC_HDR *ProcGlobal;
--
2.27.0
----Next_Part(Thu_Jan_21_12_03_48_2021_284)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="v47-0004-Shared-memory-based-stats-collector.patch"
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Use generation memory context for tuplestore.c
@ 2024-07-05 14:00 Alexander Lakhin <[email protected]>
2024-07-06 00:08 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
0 siblings, 1 reply; 5+ messages in thread
From: Alexander Lakhin @ 2024-07-05 14:00 UTC (permalink / raw)
To: David Rowley <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; PostgreSQL Developers <[email protected]>
05.07.2024 07:57, David Rowley wrote:
> Thanks for the report. I've just pushed a fix in 53abb1e0e.
Thank you, David!
Please look at another anomaly introduced with 590b045c3:
echo "
CREATE TABLE t(f int, t int);
INSERT INTO t VALUES (1, 1);
WITH RECURSIVE sg(f, t) AS (
SELECT * FROM t t1
UNION ALL
SELECT t2.* FROM t t2, sg WHERE t2.f = sg.t
) SEARCH DEPTH FIRST BY f, t SET seq
SELECT * FROM sg;
" | timeout 60 psql
triggers
TRAP: failed Assert("chunk->requested_size < oldsize"), File: "generation.c", Line: 842, PID: 830294
Best regards,
Alexander
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Use generation memory context for tuplestore.c
2024-07-05 14:00 Re: Use generation memory context for tuplestore.c Alexander Lakhin <[email protected]>
@ 2024-07-06 00:08 ` David Rowley <[email protected]>
2024-07-06 02:05 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
2024-07-06 05:41 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
0 siblings, 2 replies; 5+ messages in thread
From: David Rowley @ 2024-07-06 00:08 UTC (permalink / raw)
To: Alexander Lakhin <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; PostgreSQL Developers <[email protected]>
On Sat, 6 Jul 2024 at 02:00, Alexander Lakhin <[email protected]> wrote:
> CREATE TABLE t(f int, t int);
> INSERT INTO t VALUES (1, 1);
>
> WITH RECURSIVE sg(f, t) AS (
> SELECT * FROM t t1
> UNION ALL
> SELECT t2.* FROM t t2, sg WHERE t2.f = sg.t
> ) SEARCH DEPTH FIRST BY f, t SET seq
> SELECT * FROM sg;
> " | timeout 60 psql
>
> triggers
> TRAP: failed Assert("chunk->requested_size < oldsize"), File: "generation.c", Line: 842, PID: 830294
This seems to be a bug in GenerationRealloc().
What's happening is when we palloc(4) for the files array in
makeBufFile(), that palloc uses GenerationAlloc() and since we have
MEMORY_CONTEXT_CHECKING, the code does:
/* ensure there's always space for the sentinel byte */
chunk_size = MAXALIGN(size + 1);
resulting in chunk_size == 8. When extendBufFile() effectively does
the repalloc(file->files, 8), we call GenerationRealloc() with those 8
bytes and go into the "if (oldsize >= size)" path thinking we have
enough space already. Here both values are 8, which would be fine on
non-MEMORY_CONTEXT_CHECKING builds, but there's no space for the
sentinel byte here. set_sentinel(pointer, size) stomps on some memory,
but no crash from that. It's only a problem when extendBufFile() asks
for 12 bytes that we come back into GenerationRealloc() and trigger
the Assert(chunk->requested_size < oldsize). Both of these values are
8. The oldsize should have been large enough to store the sentinel
byte, it isn't due to the problem caused during GenerationRealloc with
8 bytes.
I also had not intended that the buffile.c stuff would use the
generation context. I'll need to fix that too, but I think I'll fix
the GenerationRealloc() first.
The attached fixes the issue. I'll stare at it a bit more and try to
decide if that's the best way to fix it.
David
Attachments:
[application/octet-stream] GenerationRealloc_fix.patch (611B, ../../CAApHDvqFt_CdJtSr+E9YLZb7jZAyRCy3hjQ+ktM+dcOFVq-xkg@mail.gmail.com/2-GenerationRealloc_fix.patch)
download | inline diff:
diff --git a/src/backend/utils/mmgr/generation.c b/src/backend/utils/mmgr/generation.c
index b858b8d0f7..a0217adbf5 100644
--- a/src/backend/utils/mmgr/generation.c
+++ b/src/backend/utils/mmgr/generation.c
@@ -855,7 +855,12 @@ GenerationRealloc(void *pointer, Size size, int flags)
*
* XXX Perhaps we should annotate this condition with unlikely()?
*/
+#ifdef MEMORY_CONTEXT_CHECKING
+ /* With MEMORY_CONTEXT_CHECKING we need an extra byte for the sentinel */
+ if (oldsize > size)
+#else
if (oldsize >= size)
+#endif
{
#ifdef MEMORY_CONTEXT_CHECKING
Size oldrequest = chunk->requested_size;
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Use generation memory context for tuplestore.c
2024-07-05 14:00 Re: Use generation memory context for tuplestore.c Alexander Lakhin <[email protected]>
2024-07-06 00:08 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
@ 2024-07-06 02:05 ` David Rowley <[email protected]>
1 sibling, 0 replies; 5+ messages in thread
From: David Rowley @ 2024-07-06 02:05 UTC (permalink / raw)
To: Alexander Lakhin <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; PostgreSQL Developers <[email protected]>
On Sat, 6 Jul 2024 at 12:08, David Rowley <[email protected]> wrote:
> The attached fixes the issue. I'll stare at it a bit more and try to
> decide if that's the best way to fix it.
I did that staring work and thought about arranging the code to reduce
the number of #ifdefs. In the end, I decided it was better to keep the
two "if" checks close together so that it's easy to see that one does
> and the other >=. Someone else's tastes may vary.
I adjusted the comment to remove the >= mention and pushed the
resulting patch and backpatched to 16, where I broke this in
0e480385e.
Thanks for the report.
David
David
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Use generation memory context for tuplestore.c
2024-07-05 14:00 Re: Use generation memory context for tuplestore.c Alexander Lakhin <[email protected]>
2024-07-06 00:08 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
@ 2024-07-06 05:41 ` David Rowley <[email protected]>
1 sibling, 0 replies; 5+ messages in thread
From: David Rowley @ 2024-07-06 05:41 UTC (permalink / raw)
To: Alexander Lakhin <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; PostgreSQL Developers <[email protected]>
On Sat, 6 Jul 2024 at 12:08, David Rowley <[email protected]> wrote:
> I also had not intended that the buffile.c stuff would use the
> generation context. I'll need to fix that too, but I think I'll fix
> the GenerationRealloc() first.
I've pushed a fix for that now too.
David
^ permalink raw reply [nested|flat] 5+ messages in thread
end of thread, other threads:[~2024-07-06 05:41 UTC | newest]
Thread overview: 5+ messages (download: mbox mbox.gz follow: Atom feed)
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2020-03-13 07:59 [PATCH v47 3/7] Make archiver process an auxiliary process Kyotaro Horiguchi <[email protected]>
2024-07-05 14:00 Re: Use generation memory context for tuplestore.c Alexander Lakhin <[email protected]>
2024-07-06 00:08 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
2024-07-06 02:05 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
2024-07-06 05:41 ` Re: Use generation memory context for tuplestore.c David Rowley <[email protected]>
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