Re: Wierd context-switching issue on Xeon

Tested the sql on Quad 2.0GHz XEON/8GB RAM:
 
During the first run, the CS shooted up more than 100k, and was randomly high/low
Second process made it consistently high 100k+
Third brought it down to anaverage 80-90k
Fourth brought it down to an average of 50-60k/s
 
By cancelling the queries one-by-one, the CS started going up again.
 
8 logical CPUs in 'top', all of them not at all too busy, load average stood around 2 all the time.
 
Thanks.
Anjan
 
-----Original Message----- 
From: Josh Berkus [mailto:josh@agliodbs.com] 
Sent: Tue 4/20/2004 12:59 PM 
To: Anjan Dave; Dirk Lutzebäck; Tom Lane 
Cc: pgsql-performance@postgreSQL.org; Neil Conway 
Subject: Re: [PERFORM] Wierd context-switching issue on Xeon



    Anjan,
    
    > Quad 2.0GHz XEON with highest load we have seen on the applications, DB
    > performing great -
    
    Can you run Tom's test?   It takes a particular pattern of data access to
    reproduce the issue.
    
    --
    Josh Berkus
    Aglio Database Solutions
    San Francisco
    
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