From: Jignesh K. Shah <J.K.Shah@Sun.COM>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Josh Berkus <josh@agliodbs.com>
Cc: pgsql-performance@postgresql.org, Alvaro Herrera <alvherre@commandprompt.com>
Subject: Re: User concurrency thresholding: where do I look?
Date: Fri, 20 Jul 2007 14:56:31 -0400
Message-ID: <46A1055F.9010304@sun.com> (raw)
In-Reply-To: <12002.1184955831@sss.pgh.pa.us>
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>
<12002.1184955831@sss.pgh.pa.us>
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
>
> ---------------------------(end of broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
> choose an index scan if your joining column's datatypes do not
> match
>
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To: pgsql-performance@postgresql.org
Cc: J.K.Shah@Sun.COM, tgl@sss.pgh.pa.us, josh@agliodbs.com, alvherre@commandprompt.com
Subject: Re: User concurrency thresholding: where do I look?
In-Reply-To: <46A1055F.9010304@sun.com>
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