Re: autovacuum starvation - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: autovacuum starvation
Date
Msg-id 20070507175910.GO3939@alvh.no-ip.org
Whole thread Raw
In response to Re: autovacuum starvation  (Jim Nasby <decibel@decibel.org>)
Responses Re: autovacuum starvation  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Jim Nasby wrote:
> On May 2, 2007, at 5:39 PM, Alvaro Herrera wrote:
> >The recently discovered autovacuum bug made me notice something  
> >that is
> >possibly critical.  The current autovacuum code makes an effort not to
> >leave workers in a "starting" state for too long, lest there be  
> >failure
> >to timely tend all databases needing vacuum.

> Isn't there some way to get the postmaster to signal the launcher?  
> Perhaps stick an error code in shared memory and send it a signal?

We could have the postmaster signal the launcher, but the signal cannot
contain much useful info because the postmaster does generally not want
to write in shared memory.

Perhaps we could have the postmaster send a SIGUSR2 signal, which would
mean "couldn't start the worker" without any other info.  Anything else
the launcher needs can be deduced from shmem state anyway.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support


pgsql-hackers by date:

Previous
From: Andrew Dunstan
Date:
Subject: Re: plperl vs. bytea
Next
From: Hiroshi Inoue
Date:
Subject: Re: [COMMITTERS] psqlodbc - psqlodbc: Put Autotools-generated files into subdirectory