Re: slru.c race condition (was Re: TRAP: FailedAssertion("!((itemid)->lp_flags

Bruce Momjian <pgman@candle.pha.pa.us>

From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: "Jim C. Nasby" <jnasby@pervasive.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Gavin Sherry <swm@linuxworld.com.au>, pgsql-hackers@postgresql.org
Date: 2005-10-31T18:17:05Z
Lists: pgsql-hackers
Tom Lane wrote:
> "Jim C. Nasby" <jnasby@pervasive.com> writes:
> > On Sun, Oct 30, 2005 at 06:17:53PM -0500, Tom Lane wrote:
> >> This won't do as a permanent patch, because it isn't guaranteed to fix
> >> the problem on machines that don't strongly order writes, but it should
> >> work on Opterons, at least well enough to confirm the diagnosis.
> 
> > Given your proposed fix on -patches, do you still need me to test this?
> 
> Yes; we still need to verify that my theory actually explains your
> problem.  Given that I'm positing that you can repeatedly hit a
> two-instruction window, this is by no means a sure thing.  We need
> it tested (and with asserts on, so that we can tell if it's fixed
> the problem or not).
> 
> > Also, is there any heap corruption risk associated with this patch?
> 
> Look, Jim, I'm trying to help you fix this.  Are you going to help or not?
> If you want some kind of written guarantee, you're not going to get one.

I think we can say Jim gets his money back if he finds a bug.  :-)

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