So here's a better stack trace for the segfault issue (again, just to
summarize, since this is a long thread, we're seeing two issues: 1) alloc
errors that do not crash the DB (although we modified postgres to panic
when this happens in our test environment, and posted a stack earlier) 2) a
postgres segfault that happens once every couple of days on our slaves.
We're still not sure if these are the same issue or not. This stack is not
perfect because it still has some things optimized out (this came from our
production database), but it's much more detailed than the last one we
posted for a segfault... hope this helps get closer to an answer on
this... I'd also be interested in knowing if the postgres experts thing
these two symptoms are likely related... or totally separate issues...
Thanks!
-B
#0 0x0000000000455dc1 in slot_deform_tuple (slot=0x53cfc20, natts=70) at
heaptuple.c:1090
1090 off = att_align_pointer(off, thisatt->attalign, -1,
(gdb) bt
#0 0x0000000000455dc1 in slot_deform_tuple (slot=0x53cfc20, natts=70) at
heaptuple.c:1090
#1 0x0000000000455fbd in slot_getallattrs (slot=0x53cfc20) at
heaptuple.c:1253
#2 0x0000000000458ac7 in printtup (slot=0x53cfc20, self=0x534f1e0) at
printtup.c:300
#3 0x000000000055bd69 in ExecutePlan (queryDesc=0x5515978,
direction=<value optimized out>, count=0)
at execMain.c:1464
#4 standard_ExecutorRun (queryDesc=0x5515978, direction=<value optimized
out>, count=0) at execMain.c:313
#5 0x0000000000623594 in PortalRunSelect (portal=0x5394f10, forward=<value
optimized out>, count=0,
dest=0x534f1e0) at pquery.c:943
#6 0x0000000000624ae0 in PortalRun (portal=0x5394f10,
count=9223372036854775807, isTopLevel=1 '\001',
dest=0x534f1e0, altdest=0x534f1e0, completionTag=0x7fff014e0640 "") at
pquery.c:787
#7 0x00000000006220f2 in exec_execute_message (argc=<value optimized out>,
argv=<value optimized out>,
username=<value optimized out>) at postgres.c:1963
#8 PostgresMain (argc=<value optimized out>, argv=<value optimized out>,
username=<value optimized out>)
at postgres.c:3983
#9 0x00000000005e6ba4 in ServerLoop () at postmaster.c:3601
#10 0x00000000005e791c in PostmasterMain (argc=5, argv=0x524cab0) at
postmaster.c:1116
#11 0x000000000058b9ae in in (argc=5, argv=<value optimized out>) at
main.c:199
