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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Excessive SQL*Net message from client waits
I'd start by being doubtful about anybody being able to work so fast that the can avoid a high percentage of time in 'sql*net from client' - in fact, it the percentage was low (when the client was a person at a terminal) I would write myself a memo to check whether the client code was executing an extreme number of very small statements behind the scenes (e.g. get all keys for a drop-down, then get each drop down by key one at a time every time the user hit the field).
It's always possible that the many layers of code at the client end are taking a surprising
However, assuming you have a truly
unreasonable loss of time on waiting for
client - I would try and isolate the problem
by using netstat and top. This can be hard
in typical environments, though.
Start up the client session -
Start netstat running on the server with
minimum snapshot time (usually one
second).
Start top (or similar) running in real time or minimum snapshot time.
Start up event 10046 at the session.
Then get the client to do something,
and watch for:
It's crude, but simple-minded, and if the client is causing the problem it may prove it quite convincingly.
Back it up with the trace file - which will record timestamps of a query coming in and results going out.
The biggest problem, usually, is that it
simply isn't realistic to get a system so
quiet that you can get just one client
running all by itself with nothing else going
on.
In your particular case, I have to sya that I have noticed that Java can use a surprising amount of CPU sometimes.
Regards
Jonathan Lewis
http://www.jlcomp.demon.co.uk
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> Good point, but what if each user only has a single session?
>
> Not that I've noticed this exact same situation here on one of our
> Engineering support databases whose clients are Java, and I'm not
wondering
> if it has something to do with the application or if I can possibly
speed it
> up with tweaks to SDU/TDU. I'm just wondering... ;)
>
-- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Jonathan Lewis INET: jonathan_at_jlcomp.demon.co.uk Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Thu Mar 13 2003 - 11:19:22 CST
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