Horton

Re: Wierd context-switching issue on Xeon

Dave Cramer <pg@fastcrypt.com>

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From: Dave Cramer <pg@fastcrypt.com>
To: Dirk_Lutzebäck <lutzeb@aeccom.com>
Cc: ohp@pyrenet.fr, Tom Lane <tgl@sss.pgh.pa.us>, Josh Berkus <josh@agliodbs.com>, Joe Conway <mail@joeconway.com>, "scott.marlowe" <scott.marlowe@ihs.com>, Bruce Momjian <pgman@candle.pha.pa.us>, pgsql-performance@postgresql.org, Neil Conway <neilc@samurai.com>
Date: 2004-04-21T15:05:31Z
Lists: pgsql-performance 
After some testing if you use the current head code for s_lock.c which
has some mods in it to alleviate this situation, and change
SPINS_PER_DELAY to 10 you can drastically reduce the cs with tom's test.
I am seeing a slight degradation in throughput using pgbench -c 10 -t
1000 but it might be liveable, considering the alternative is unbearable
in some situations.

Can anyone else replicate my results?

Dave
On Wed, 2004-04-21 at 08:10, Dirk_Lutzebäck wrote:
> It is intended to run indefinately.
> 
> Dirk
> 
> ohp@pyrenet.fr wrote:
> 
> >How long is this test supposed to run?
> >
> >I've launched just 1 for testing, the plan seems horrible; the test is cpu
> >bound and hasn't finished yet after 17:02 min of CPU time, dual XEON 2.6G
> >Unixware 713
> >
> >The machine is a Fujitsu-Siemens TX 200 server
> >  
> >
> 
> 
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-- 
Dave Cramer
519 939 0336
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