Re: CPU bound - Mailing list pgsql-performance

From Jeremy Harris
Subject Re: CPU bound
Date
Msg-id 4D0F998E.7060007@wizmail.org
Whole thread Raw
In response to Re: CPU bound  (Kenneth Marshall <ktm@rice.edu>)
List pgsql-performance
On 2010-12-20 15:48, Kenneth Marshall wrote:
>> And how exactly, given that the kernel does not know whether the CPU is
>> active or waiting on ram, could an application do so?
>>
>
> Exactly. I have only seen this data from hardware emulators. It would
> be nice to have...  :)

There's no reason that the cpu hardware couldn't gather such, and
IMHO it's be dead useful, at least at the outermost cache level
(preferably separately at each level).   But people have trouble
understanding vmstat already....

Note that dtrace *can* get to the cpu performance counters,
just that the kernel doesn't routinely account for all that info
per-process as routine.   I'd expect IBM to have equivalent
facilities.

--
Jeremy

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