Re: pg_terminate_backend idea

On Tue, 2005-06-21 at 23:34 -0400, Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Tom Lane wrote:
> >> In any case the correct way to solve the problem is to find out what's
> >> being left corrupt by SIGTERM, rather than install more messiness in
> >> order to avoid facing the real issue ...
> 
> > I am confused.  Are you talking about the client SIGTERM or the server? 
> 
> I am talking about Rod Taylor's reports that SIGTERM'ing individual
> backends tends to lead to "lock table corrupted" crashes awhile later.
> Now, I've been playing the part of Chicken Little on this for awhile,
> but seeing an actual report of problems from the field certainly
> strengthens my feelings about it.

Bringing this thread back to life.

I have not seen a lock table corruption issue with SIGTERM in 8.1 on
Solaris/Sun IV, Linux/AMD64, or Linux/Intel. I don't recall seeing one
on 8.0.3 either though I'm pretty sure there were several on 8.0.1.

There are times when locks for a process hang around for a few minutes
before getting cleared. I don't recall whether they were ungranted table
locks or entries waiting on a transaction ID lock, but the source was
Slony and a large pg_listener structure with more than 20000 pages (yes,
pages not tuples).

I have also seen processes refusing to acknowledge the signal and exit
during btree index builds, but that's not a data corruption issue.
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