Re: Slow dump with pg_dump/pg_restore ? How to improve ?

From: Soeren Gerlach <soeren(at)all-about-shift(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Slow dump with pg_dump/pg_restore ? How to improve ?
Date: 2004-07-01 21:08:19
Message-ID: 200407012308.19036.soeren@all-about-shift.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general


> Soeren Gerlach <soeren(at)all-about-shift(dot)com> writes:
> > * pg_dump takes 2/3 of the [single] CPU, postmaster the other 1/3 for
> > both dumps
>
> Really!? Hmm, that seems fairly backwards ... thinks ...
>
> In the -Fc case this makes some amount of sense because pg_dump runs
> gzip-style compression on the data (which is why the output file is
> so much smaller). But for plain text dump, pg_dump should be just
> pushing the data straight through to stdout; it really ought not take
> much CPU as far as I can see. There may be some simple performance
> glitch involved there. Are you interested in recompiling with -pg
> and getting a gprof profile of pg_dump?

Yes I'am but I'm a little short on time ,-)) In fact I'm glad to d'l a
ready-to-run archive for Debian Woody. In two weeks I'll have some time to
check this issue with my own compiled versions, until then I'm just
interested ,-))
Today I upgraded to 7.4.3 from 7.4.1 but this did not change anything real.
Do you have numbers in respect to speed (rows per second) for comparison
available. I.e. dump on a single CPU machine which quite fast drives?

Regards,
Soeren

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Alexander Cohen 2004-07-01 21:09:23 row level grants
Previous Message Scott Marlowe 2004-07-01 21:00:24 Re: max_fsm_pages