From: Dalibor Sramek <dali@insula.cz>
To: Merlin Moncure <merlin.moncure@rcsonline.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Low performance on Windows problem
Date: Wed, 14 Sep 2005 15:02:22 +0200
Message-ID: <20050914130221.GA18466@www.epot.cz> (raw)
In-Reply-To: <6EE64EF3AB31D5448D0007DD34EEB3417DD31A@Herge.rcsinc.local>
References: <6EE64EF3AB31D5448D0007DD34EEB3417DD31A@Herge.rcsinc.local>
On Tue, Sep 13, 2005 at 11:05:00AM -0400, Merlin Moncure wrote:
> 5. do select array_accum(q::text) from generate_series(1,10000) q;
I made the tests you suggested and the pattern is clear. The difference
between local and remote command execution is caused by moving data over
the network. E.g. the command above takes 700 ms locally and 1500 ms
remotely. Remote explain analyze takes exactly the 700 ms.
I downloaded PCATTCP - http://www.pcausa.com/Utilities/pcattcp.htm
and the measured throughput between the two machines is over 10000 kB/s.
PCATTCP allows setting TCP_NODELAY but it had no effect on the transfer
speed. So the difference between local and remote execution should IMHO stay
in the 10 ms range. Definitely not 800 ms. The 8.1 has the same problem.
Just for the record: the server PC is Dell Precision 330 with 3Com 3C920
integrated network card. OS MS Windows Professional 2002 with service pack
2. There is Symantec Antivirus installed - which I have (hopefully)
completely disabled.
Thanks for any help
Dalibor Sramek
--
Dalibor Sramek http://www.insula.cz/dali \ In the eyes of cats
/ dalibor.sramek@insula.cz \ all things
/ >H blog http://www.transhumanismus.cz/blog.php \ belong to cats.
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To: pgsql-performance@postgresql.org
Cc: dali@insula.cz, merlin.moncure@rcsonline.com
Subject: Re: Low performance on Windows problem
In-Reply-To: <20050914130221.GA18466@www.epot.cz>
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