To: Bjorn Solberg <bjorn@geocities.com>
cc: pgsql-interfaces@postgresql.org
Subject: Re: Backend dies for DBI 
In-reply-to: <m3k862d2nk.fsf@pacbell.net> 
References: <m3k862d2nk.fsf@pacbell.net>
Comments: In-reply-to Bjorn Solberg <bjorn@geocities.com>
	message dated "06 Mar 2001 13:10:39 -0800"
Date: Wed, 07 Mar 2001 19:49:05 -0500
Message-ID: <22575.984012545@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Bjorn Solberg <bjorn@geocities.com> writes:
> The log file from postmaster simply says:

> --->
> StartTransactionCommand
> [...]
> ProcessQuery
> CommitTransactionCommand
> proc_exit(0)
> shmem_exit(0)
> exit(0)
> /usr/local/pgsql/bin/postmaster: reaping dead processes...
> /usr/local/pgsql/bin/postmaster: CleanupProc: pid 1297 exited with status 0
> proc_exit(0)
> shmem_exit(0)
> exit(0)
> /usr/local/pgsql/bin/postmaster: reaping dead processes...
> /usr/local/pgsql/bin/postmaster: CleanupProc: pid 1298 exited with status 0
> ---<

This looks absolutely normal --- there's no evidence here for anything
except normal backend exit.  At least the backend thinks it's normal.
You should be looking for client or protocol-level problems.

> DBI (I think) sometimes output a message like "Backend message type 0x50
> arrived while idle".  This can happen several times, and the crash does
> not occur directly following any of the messages.

This may indicate running out of memory for a query result on the client
side; libpq is not very graceful about dealing with that :-(.  You
should check on the sizes of query results you are fetching and the
amount of memory available to your DBI applications.  Fetching a few
rows at a time via a CURSOR is a good workaround if that seems to be
the problem.

			regards, tom lane