Date: Fri, 20 Jul 2007 14:56:31 -0400
From: "Jignesh K. Shah" <J.K.Shah@Sun.COM>
Subject: Re: User concurrency thresholding: where do I look?
In-reply-to: <12002.1184955831@sss.pgh.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Josh Berkus <josh@agliodbs.com>, pgsql-performance@postgresql.org,
	Alvaro Herrera <alvherre@commandprompt.com>
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Organization: Sun Microsystems
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References: <200707190828.59088.josh@agliodbs.com>
	<200707191819.13899.josh@agliodbs.com> <15685.1184895926@sss.pgh.pa.us>
	<200707192138.39679.josh@agliodbs.com> <46A0FA31.2080208@sun.com>
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Yes I did see increase in context switches and CPU migrations at that 
point using mpstat.

Regards,
Jignesh


Tom Lane wrote:
> "Jignesh K. Shah" <J.K.Shah@Sun.COM> writes:
>   
>> There are no hard failures reported anywhere. Log min durations does 
>> show that queries are now slowing down and taking longer.
>> OS is not swapping and also eliminated IO  by putting the whole database 
>> on /tmp
>>     
>
> Hmm.  Do you see any evidence of a context swap storm (ie, a drastic
> increase in the context swaps/second reading reported by vmstat)?
>
> 			regards, tom lane
>
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