Re: Autovacuum daemon terminated by signal 11

Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> Tom Lane wrote:
>> Hmm. This isn't very trustworthy for lack of debug symbols (what we're
>> probably looking at are the nearest global function names before the
>> actual locations).

> The lack of debug symbols makes this all mere guesses though. The
> backtrace did not make a lot of sense to me.

I read it like this:

#0 0x0827441d in MemoryContextAlloc () <-- real
#1 0x08274467 in MemoryContextStrdup () <-- real
#2 0x0826501c in database_getflatfilename () <-- real
#3 0x0826504e in database_getflatfilename () <-- must be write_database_file
#4 0x08265ec1 in AtEOXact_UpdateFlatFiles () <-- real
#5 0x080a9111 in RecordTransactionCommit () <-- must be CommitTransaction
#6 0x080a93a7 in CommitTransactionCommand () <-- real
#7 0x081a6c3b in autovac_stopped () <-- must be process_whole_db
#8 0x081a75cd in autovac_start () <-- real
#9 0x081ae33c in ClosePostmasterPorts () <-- must be ServerLoop
#10 0x081af058 in PostmasterMain ()
#11 0x0816b3e2 in main ()

although this requires one or two leaps of faith about single-call
static functions getting inlined so that they don't produce a callstack
entry (in particular that must have happened to AutoVacMain). In any
case, it's very hard to see how MemoryContextAlloc would dump core
unless the method pointer of the context it was pointed to was
clobbered. So I'm pretty sure that's what happened, and now we must
work backwards to how it happened,

Justin, it's entirely possible that the only way we'll figure it out
is for a developer to go poking at the entrails. Are you in a position
to give Alvaro or me ssh access to your test machine?

regards, tom lane