Re: Longer and longer updates - Mailing list pgsql-general

From ender
Subject Re: Longer and longer updates
Date
Msg-id 01020521525101.00635@linux
Whole thread Raw
In response to Re: Longer and longer updates  (Alfred Perlstein <bright@wintelcom.net>)
List pgsql-general
if you're doing updates in a single transaction, you'll realize speed gains
by distributing the updates into multiple transactions. postgres won't have
to keep multiple copies that way.

hth

kapil


> >
> > 3) executed this statement tons of times:
> >
> >    update test set data=1234 where key=1
> >
> > Here are the results -- it's pretty discouraging, I hope I'm making some
> > simple mistake, or maybe this is expected behavior for some reason?
> >
> > After this many updates        ...it took this long for 1000 more updates
> > -----------------------        ------------------------------------------
> >         0                                   10880 ms
> >       5,000                                 10549 ms
> >      10,000                                 17380 ms
> >      15,000                                 20040 ms
> >      20,000                                 20060 ms
> >      25,000                                 20589 ms
> >      30,000                                 30749 ms
> >      35,000                                 30350 ms
> >      40,000                                 30910 ms
> >      45,000                                 37570 ms
> >      50,000                                 40379 ms
> >
> > This seems to be independent of starting and stopping my client and the
> > postmaster, running vacuum, praying, etc.  I'm on RedHat6.2
> > running with the 7.1beta4 rpms.

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