Re: odd postgresql performance (excessive lseek) - Mailing list pgsql-performance

From Merlin Moncure
Subject Re: odd postgresql performance (excessive lseek)
Date
Msg-id AANLkTimUp6VmXRD2-U4Gfp1L5KS_fq3OJfOMHgE6k6oz@mail.gmail.com
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In response to Re: odd postgresql performance (excessive lseek)  (Jon Nelson <jnelson+pgsql@jamponi.net>)
Responses Re: odd postgresql performance (excessive lseek)  (Jon Nelson <jnelson+pgsql@jamponi.net>)
List pgsql-performance
On Tue, Oct 19, 2010 at 9:10 AM, Jon Nelson <jnelson+pgsql@jamponi.net> wrote:
> No replies?
>
> This is another situation where using pread would have saved a lot of
> time and sped things up a bit, but failing that, keeping track of the
> file position ourselves and only lseek'ing when necessary would also
> help. Postgresql was spending 37% of it's time in redundant lseek!

37% of cpu time?  Is that according to strace -T? how did you measure it?

merlin

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