Re: Hardware recommendations to scale to silly load

Nitpicking --

Perhaps the 4th data line is meant to be:
        Inserts in separate transactions         2500 inserts/second
                   ^^^^^^^^^^^^^^^^^^^^^^^
??


Greg Williamson

-----Original Message-----
From:    Bruce Momjian [mailto:pgman@candle.pha.pa.us]
Sent:    Tue 9/9/2003 8:25 PM
To:    Matt Clark
Cc:    Ron Johnson; PgSQL Performance ML
Subject:    Re: [PERFORM] Hardware recommendations to scale to silly load

Matt Clark wrote:
> > Just a data point, but on my Dual Xeon 2.4Gig machine with a 10k SCSI
> > drive I can do 4k inserts/second if I turn fsync off.  If you have a
> > battery-backed controller, you should be able to do the same.  (You will
> > not need to turn fsync off --- fsync will just be fast because of the
> > disk drive RAM).
> >
> > Am I missing something?
>
> I think Ron asked this, but I will too, is that 4k inserts in
> one transaction or 4k transactions each with one insert?
>
> fsync is very much faster (as are all random writes) with the
> write-back cache, but I'd hazard a guess that it's still not
> nearly as fast as turning fsync off altogether.  I'll do a test
> perhaps...

Sorry to be replying late.  Here is what I found.

fsync on
        Inserts all in one transaction         3700 inserts/second
        Inserts in separate transactions        870 inserts/second

fsync off
        Inserts all in one transaction         3700 inserts/second
        Inserts all in one transaction         2500 inserts/second

ECPG test program attached.

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