Re: terminated by signal 6 problem

From: Joe Conway <mail(at)joeconway(dot)com>
To: Jan Wieck <JanWieck(at)Yahoo(dot)com>
Cc: "Hackers (PostgreSQL)" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: terminated by signal 6 problem
Date: 2004-08-11 20:54:30
Message-ID: 411A8786.2090402@joeconway.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Jan Wieck wrote:
> I have seen similar when running under heavy load with high frequent
> insert+delete+vacuum. What happens is that adding another item to an

This fits the profile of this application perfectly.

> index page in the btree access method fails. It seems to me that the
> decision to add an item to a page and the real work of actually adding
> it are not atomic, so that under certain race conditions two backends
> make the same decision while one would have to split the page.

Hmmm, sounds like a somewhat serious issue. Any thoughts on a fix, or
even a reliable workaround?

> Restarting the whole postmaster looks like overreacting also, but it
> apparently fixes the problem since the index is just fine and retrying
> the insert afterwards works.

But it is disruptive to an application that collects data 24 x 365 at
this kind of load. I've been discussing with the developers ways to
eliminate the delete and most of the vacuum load (in favor of "work"
tables and TRUNCATE), so maybe this issue will force that change.

Thanks,

Joe

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Tom Lane 2004-08-11 21:22:29 Re: terminated by signal 6 problem
Previous Message Tom Lane 2004-08-11 20:43:08 Re: will PITR in 8.0 be usable for "hot spare"/"log shipping" type of replication