On Fri, May 28, 2010 at 4:04 AM, Joachim Worringen <joachim.worringen@xxxxxxxx> wrote: > On 05/26/2010 06:03 PM, Joachim Worringen wrote: >> >> Am 25.05.2010 12:41, schrieb Andres Freund: >>> >>> On Tuesday 25 May 2010 11:00:24 Joachim Worringen wrote: >>>> >>>> Thanks. So, the Write-Ahead-Logging (being used or not) does not matter? >>> >>> It does matter quite significantly in my experience. Both from an io >>> and a cpu >>> overhead perspective. >> >> O.k., looks as if I have to make my own experience... I'll let you know >> if possible. > > As promised, I did a tiny benchmark - basically, 8 empty tables are filled > with 100k rows each within 8 transactions (somewhat typically for my > application). The test machine has 4 cores, 64G RAM and RAID1 10k drives for > data. > > # INSERTs into a TEMPORARY table: > [joachim@testsrv scaling]$ time pb query -d scaling_qry_1.xml > > real 3m18.242s > user 1m59.074s > sys 1m51.001s > > # INSERTs into a standard table: > [joachim@testsrv scaling]$ time pb query -d scaling_qry_1.xml > > real 3m35.090s > user 2m5.295s > sys 2m2.307s > > Thus, there is a slight hit of about 10% (which may even be within > meausrement variations) - your milage will vary. > > Joachim > > > -- > Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance > I think it would be interesting to create a ram disk and insert into it. In the MySQL community even thought MyISAM has fallen out of use the Memory table (based on MyISAM) is still somewhat used. -- Rob Wultsch wultsch@xxxxxxxxx -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
