Re: Postgres 9.1: Adding rows to table causing too much latency in other queries

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Jesper Krogh <jesper(at)krogh(dot)cc>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: Postgres 9.1: Adding rows to table causing too much latency in other queries
Date: 2011-12-19 20:50:02
Message-ID: 16490.1324327802@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Jesper Krogh <jesper(at)krogh(dot)cc> writes:
> I have to say that I consistently have to turn "fastupdate" off for
> our heavily updated gin-indexes. The overall performance gain
> may be measurable, but its not intolerable without. The spikes seen
> from the applications, when cleanup happens. Either in the foreground
> or in the background are not tolerable. (multiple seconds).

Well, that's why there's a provision to turn it off: if response time
spikes are a bigger deal to you than overall performance, you probably
don't want bulk updates.

The theory is that you should be able to tune things so that the bulk
updates are done by autovacuum, but if you can't get that to work
sufficiently reliably, fastupdate=off is the best answer.

regards, tom lane

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2011-12-19 21:11:49 Re: Review: Non-inheritable check constraints
Previous Message Tom Lane 2011-12-19 20:47:16 Re: Postgres 9.1: Adding rows to table causing too much latency in other queries