From: Marc Cousin <mcousin@sigma.fr>
Organization: Sigma Informatique
To: "Magnus Hagander" <mha@sollentuna.net>
Subject: Re: insert performance for win32
Date: Wed, 2 Nov 2005 15:47:28 +0100
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Cc: "Merlin Moncure" <merlin.moncure@rcsonline.com>,
	pgsql-performance@postgresql.org, "Qingqing Zhou" <zhouqq@cs.toronto.edu>
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Le Mercredi 02 Novembre 2005 14:54, Magnus Hagander a =E9crit=A0:
> > > I've done the tests with rc1. This is still as slow on windows ...
> >
> > about
> >
> > > 6-10
> > > times slower thant linux (via Ip socket). (depending on
> >
> > using prepared
> >
> > > queries, etc...)
> > >
> > > By the way, we've tried to insert into the windows database from a
> >
> > linux
> >
> > > psql
> > > client, via the network. In this configuration, inserting is only
> >
> > about 2
> >
> > > times slower than inserting locally (the linux client had a
> >
> > slower CPU
> >
> > > 1700Mhz agains 3000).
> > > Could it be related to a problem in the windows psql client ?
> >
> > [OK, I'm bringing this back on-list, and bringing it to
> > QingQing's attention, who I secretly hope is the right person
> > to be looking at this problem :)]
> >
> > Just to recap Marc and I have been looking at the performance
> > disparity between windows and linux for a single transaction
> > statement by statement insert on a very narrow table with no
> > keys from a remote client.  Marc's observations showed (and I
> > verified) that windows is much slower in this case than it
> > should be.  I gprof'ed both the psql client and the server
> > during the insert and didn't see anything seriously out of
> > order...unfortunately QQ's latest win32 performance tweaks
> > haven't helped.
> >
> > Marc's observation that by switching to a linux client drops
> > time down drastically is really intersing!
>
> Could this be a case of the network being slow, as we've seen a couple
> of times before? And if you run psql on the local box, you get it
> double.
>
> Do you get a speed difference between the local windows box and a remote
> wnidows box?
>
> //Magnus
The Windows-Windows test is local (via loopback interface)
The Linux (client) - Windows (server) is via network (100Mbits)

I can't test with 2 windows box ... I haven't got that much (all machines=20
linux, except the test one...)