Re: BUG #5269: postgres backend terminates with SIGSEGV - Mailing list pgsql-bugs

From Justin Pitts
Subject Re: BUG #5269: postgres backend terminates with SIGSEGV
Date
Msg-id F7ACA758-1E26-4413-B6E3-DFC5EA6B370E@bplglobal.net
Whole thread Raw
In response to Re: BUG #5269: postgres backend terminates with SIGSEGV  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-bugs
On Jan 14, 2010, at 10:44 AM, Tom Lane wrote:

> Justin Pitts <jpitts@bplglobal.net> writes:
>> On Jan 14, 2010, at 10:16 AM, Tom Lane wrote:
>>> The 100 temp table creations probably will do that just fine.
>=20
>> Is there a way to verify this?
>=20
> You could add an elog(LOG, "message") into ResetPlanCache so you could
> tell when it had been called.
>=20

Done. Sometimes I see it, sometimes not.

>> I don't follow. Are you suggesting I begin another transaction on connec=
tion 1 with a read, and that
>> would provoke the crash?
>=20
> Yes.  The rollback only sets the stage for the next transaction to try
> to use a snapshot that isn't there anymore.
>=20

Oh, duh. A read from the same session that rolled-back. That didn't get it =
working (failing?) however.

Running concurrent instances of this test reliably provokes the crash on un=
-patched 8.4.2.
They do not provoke a crash with the patch. That's what i was looking for.

Thanks!

>             regards, tom lane

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