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Re: Simple query takes a long time on win2K

From: "A(dot) Mous" <a(dot)mous(at)shaw(dot)ca>
To: 'Magnus Hagander' <mha(at)sollentuna(dot)net>,'Tom Lane' <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: 'Richard Huxton' <dev(at)archonet(dot)com>,pgsql-general(at)postgresql(dot)org,"'Joshua D(dot) Drake'" <jd(at)commandprompt(dot)com>,'Lincoln Yeoh' <lyeoh(at)pop(dot)jaring(dot)my>,pgsql-hackers-win32(at)postgresql(dot)org
Subject: Re: Simple query takes a long time on win2K
Date: 2005-03-24 03:49:22
Message-ID: 007501c53024$7764d560$6500a8c0@PETER (view raw or flat)
Thread:
Lists: pgsql-generalpgsql-hackers-win32
Thank you all for your input, and thanks about the tip on ethereal - cool
program.  Here's what I've found out from today's testing:

The total size of the recordset that is being served up is about 500kb.
When serving across a network, the time to deliver the records to the client
is largely dependent on the hardware doing the serving (as expected) and
regardless of which OS (Win 2K pro or XP pro).  The thing that really threw
me off, and still does is when the same data is served up locally.  In this
case, all test win2K machines (Celeron 400 up to pIII 800) retrieved the
data from disk in under 100ms but took an additional 4000ms to send to the
local client.  This is observed even if QoS packet scheduler is installed.
By contrast, Win XP serves up locally nice and fast, even when installed on
exactly the same hardware that was used for the win2K test.

Thanks to all for your help and insight on this one, although I'm still
puzzled by the behaviour on the win2K boxes serving locally.

Cheers.





-----Original Message-----
From: Magnus Hagander [mailto:mha(at)sollentuna(dot)net] 
Sent: March 23, 2005 12:04 PM
To: Tom Lane; A. Mous
Cc: Richard Huxton; pgsql-general(at)postgresql(dot)org; Joshua D. Drake; Lincoln
Yeoh; pgsql-hackers-win32(at)postgresql(dot)org
Subject: RE: [GENERAL] Simple query takes a long time on win2K

> > The confusing thing for me is that so far, the only 
> consistent pattern 
> > here is that machines running win2k Pro take roughly 4 seconds to 
> > deliver the data to the client, while win XP machines perform much 
> > better (<200ms to deliver recordset).  I've tried installing QoS 
> > packet scheduler on win2K pro machines to no avail.
> 
> I really thought the QoS thing would be it.  Maybe there was 
> some other thing to do, configuration-wise, to make that do 
> its thing properly?
> 
> If you could reproduce this behavior across the network I 
> would tell you to get out a packet analyzer (ethereal or some 
> such) and sniff the traffic to learn more.  Are there any 
> programs that can sniff local TCP traffic on win2k?

Microsoft ships a network monitor with Win2k Server. Otherwise, just get
ethereal, it works perfectly on win2k.

//Magnus


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