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Date:      Sun, 7 Mar 2004 17:34:44 +0200
From:      Valentin Nechayev <netch@ivb.nn.kiev.ua>
To:        ticso@cicely.de
Cc:        freebsd-hackers@freebsd.org
Subject:   Re: how to get cpu states more than once a second?
Message-ID:  <20040307153444.GA1355@iv.nn.kiev.ua>
In-Reply-To: <20040303062730.GK44313@cicely12.cicely.de>
References:  <20040303062730.GK44313@cicely12.cicely.de>

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 Wed, Mar 03, 2004 at 07:27:31, ticso (Bernd Walter) wrote about "how to get cpu states more than once a second?": 

BW> Currently I get the states via kern.cp_time, but this only allows
BW> a granularity of a single second and I need something around 50-100ms.
BW> Application is a LED bargraph which doesn't have the intended effect
BW> with just a single update per second.

Real granularity for its is statclock rate (on x86, usually 128 or 1024).
But one should know that short period states are too inexact; there is
interferention between periodic states and statclock rate which can lead
to temporary distortions; e.g. inadequately high interrupt time reporting
during 1-2 seconds.



-netch-



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