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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Does Ada tasking profit from multi-core cpus?
Date: Wed, 7 Mar 2007 23:21:04 -0600
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Date: 2007-03-07T23:21:04-06:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
news:1lq9zxgrnvfjx$.17ip3w3ei4xdb.dlg@40tude.net...
...
> Just a side note, the Windows API GetThreadTimes (which the viewer
> apparently uses) is corrupted. It counts complete time quants rather than
> the  performance counter ticks. So, potentially you could observe 1% under
> factual 99% CPU load. The bug should appear for threads performing much
> synchronization, because they leave the processor before the current quant
> expiration.

I wouldn't call it "corrupted"; it's just not very accurate (given that it
can only register time with a granularity of 0.01 sec). I don't think there
is any other way to find out CPU use, though, as the performance counter
provides wall time and thus isn't very useful to find out how much a thread
is running. (I've tried to figure out how to implement Ada.Execution_Time on
Windows...)

                                       Randy.