I have a PostgreSQL 13 instance that keeps crashing:
LOG: server process (PID 10722) was terminated by signal 11: Segmentation fault
DETAIL: Failed process was running: COMMIT
LOG: terminating any other active server processes
WARNING: terminating connection because of crash of another server process
DETAIL: The postmaster has commanded this server process to roll back the current transaction and exit, because another server process exited abnormally and possibly corrupted shared memory.
I've updated /etc/postgresql/13/main/pg_ctl.conf to include core dumps
pg_ctl_options = '--core-files'
and restarted postgresql service. Now it seems to allow core dumps:
$ for f in `pgrep postgres`; do cat /proc/$f/limits | grep core; done
Max core file size unlimited unlimited bytes
gdb backtrace gives following output
$ gdb /usr/lib/postgresql/13/bin/postgres 13/main/core.postgres.12264
Program terminated with signal SIGSEGV, Segmentation fault.
#0 slot_deform_heap_tuple (natts=5, offp=0x557cc2e60720, tuple=<optimized out>, slot=0x557cc2e606d8) at ./build/../src/backend/executor/execTuples.c:930
930 ./build/../src/backend/executor/execTuples.c: No such file or directory.
(gdb) bt
#0 slot_deform_heap_tuple (natts=5, offp=0x557cc2e60720, tuple=<optimized out>, slot=0x557cc2e606d8) at ./build/../src/backend/executor/execTuples.c:930
#1 tts_buffer_heap_getsomeattrs (slot=0x557cc2e606d8, natts=5) at ./build/../src/backend/executor/execTuples.c:695
#2 0x0000557cc1d3998c in slot_getsomeattrs_int (slot=slot@entry=0x557cc2e606d8, attnum=5) at ./build/../src/backend/executor/execTuples.c:1912
#3 0x0000557cc1d28fba in slot_getsomeattrs (attnum=<optimized out>, slot=0x557cc2e606d8) at ./build/../src/include/executor/tuptable.h:344
#4 ExecInterpExpr (state=0x557cc2e620a8, econtext=0x557cc2ea1768, isnull=<optimized out>) at ./build/../src/backend/executor/execExprInterp.c:482
#5 0x0000557cc1d5548d in ExecEvalExprSwitchContext (isNull=0x7ffdd2599507, econtext=0x557cc2ea1768, state=0x557cc2e620a8) at ./build/../src/include/executor/executor.h:322
#6 ExecQual (econtext=0x557cc2ea1768, state=0x557cc2e620a8) at ./build/../src/include/executor/executor.h:391
#7 MJFillInner (node=0x557cc2ea1558) at ./build/../src/backend/executor/nodeMergejoin.c:494
#8 0x0000557cc1d55ce8 in ExecMergeJoin (pstate=0x557cc2ea1558) at ./build/../src/backend/executor/nodeMergejoin.c:1353
#9 0x0000557cc1d2cc83 in ExecProcNode (node=0x557cc2ea1558) at ./build/../src/include/executor/executor.h:248
#10 ExecutePlan (execute_once=<optimized out>, dest=0x557cc2e1a630, direction=<optimized out>, numberTuples=0, sendTuples=<optimized out>, operation=CMD_SELECT, use_parallel_mode=<optimized out>, planstate=0x557cc2ea1558,
estate=0x557cc2ea12f8) at ./build/../src/backend/executor/execMain.c:1632
#11 standard_ExecutorRun (queryDesc=0x557cc2e1a5a0, direction=<optimized out>, count=0, execute_once=<optimized out>) at ./build/../src/backend/executor/execMain.c:350
#12 0x00007f0ec05ae09d in pgss_ExecutorRun (queryDesc=0x557cc2e1a5a0, direction=ForwardScanDirection, count=0, execute_once=<optimized out>) at ./build/../contrib/pg_stat_statements/pg_stat_statements.c:1045
#13 0x0000557cc1cdbcd4 in PersistHoldablePortal (portal=portal@entry=0x557cc2d44b78) at ./build/../src/backend/commands/portalcmds.c:407
#14 0x0000557cc1ff95f9 in HoldPortal (portal=portal@entry=0x557cc2d44b78) at ./build/../src/backend/utils/mmgr/portalmem.c:642
#15 0x0000557cc1ff9e7d in PreCommit_Portals (isPrepare=isPrepare@entry=false) at ./build/../src/backend/utils/mmgr/portalmem.c:738
#16 0x0000557cc1c001c4 in CommitTransaction () at ./build/../src/backend/access/transam/xact.c:2087
#17 0x0000557cc1c015d5 in CommitTransactionCommand () at ./build/../src/backend/access/transam/xact.c:3085
#18 0x0000557cc1ea211d in finish_xact_command () at ./build/../src/backend/tcop/postgres.c:2662
#19 0x0000557cc1ea4703 in exec_simple_query (query_string=0x557cc2c9cd28 "COMMIT") at ./build/../src/backend/tcop/postgres.c:1264
#20 0x0000557cc1ea6143 in PostgresMain (argc=<optimized out>, argv=argv@entry=0x557cc2cf6c68, dbname=<optimized out>, username=<optimized out>) at ./build/../src/backend/tcop/postgres.c:4339
#21 0x0000557cc1e25bcd in BackendRun (port=0x557cc2ce94d0, port=0x557cc2ce94d0) at ./build/../src/backend/postmaster/postmaster.c:4526
#22 BackendStartup (port=0x557cc2ce94d0) at ./build/../src/backend/postmaster/postmaster.c:4210
#23 ServerLoop () at ./build/../src/backend/postmaster/postmaster.c:1739
#24 0x0000557cc1e26b41 in PostmasterMain (argc=5, argv=<optimized out>) at ./build/../src/backend/postmaster/postmaster.c:1412
#25 0x0000557cc1b70f4f in main (argc=5, argv=0x557cc2c96c30) at ./build/../src/backend/main/main.c:210
Adding log_statement = 'all' to /etc/postgresql/13/main/postgresql.conf doesn't really help, as postmaster terminates all processes immediately and the query doesn't get written to logs.
here's strace output after running COMMIT
[pid 20006] pwrite64(29, "COMMIT", 6, 15936) = 6
[pid 20006] pwrite64(29, "\0", 1, 15942) = 1
[pid 20006] close(29) = 0
[pid 20006] --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x10} ---
[pid 20006] +++ killed by SIGSEGV (core dumped) +++
<... select resumed> ) = ? ERESTARTNOHAND (To be restarted if no handler)
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_DUMPED, si_pid=20006, si_uid=108, si_status=SIGSEGV, si_utime=0, si_stime=0} ---
wait4(-1, [{WIFSIGNALED(s) && WTERMSIG(s) == SIGSEGV && WCOREDUMP(s)}], WNOHANG, NULL) = 20006
write(2, "2021-09-08 13:38:51.853 UTC [299"..., 198) = 198
write(2, "2021-09-08 13:38:51.853 UTC [299"..., 88) = 88
kill(19324, SIGQUIT) = 0
kill(-19324, SIGQUIT) = 0
kill(19331, SIGQUIT) = 0
kill(-19331, SIGQUIT) = 0
kill(19320, SIGQUIT) = 0
kill(-19320, SIGQUIT) = 0
kill(19319, SIGQUIT) = 0
kill(-19319, SIGQUIT) = 0
kill(19321, SIGQUIT) = 0
kill(-19321, SIGQUIT) = 0
kill(19322, SIGQUIT) = 0
kill(-19322, SIGQUIT) = 0
kill(19323, SIGQUIT) = 0
kill(-19323, SIGQUIT) = 0
wait4(-1, 0x7ffe90814374, WNOHANG, NULL) = 0
rt_sigreturn({mask=[]}) = -1 EINTR (Interrupted system call)
rt_sigprocmask(SIG_SETMASK, ~[ILL TRAP ABRT BUS FPE SEGV CONT SYS RTMIN RT_1], NULL, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
select(7, [5 6], NULL, NULL, {tv_sec=5, tv_usec=0}) = ? ERESTARTNOHAND (To be restarted if no handler)
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=19320, si_uid=108, si_status=2, si_utime=14, si_stime=3} ---
Is there a way how to trace back the exact SQL query that was executed?
