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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Ada.Execution_Time
Date: Tue, 28 Dec 2010 16:18:11 +0000
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> Yes, this thing. In our case it was Pentium VxWorks 6.x. (The PPC we
> used prior to it had poor performance) The problem was that
> Ada.Real_Time.Clock had the accuracy of the clock interrupts,
> i.e. 1ms, which is by all accounts catastrophic for a 1.7GHz
> processor. You can switch some tasks forth and back between two clock
> changes.

Our experience was that where there are timing constraints to be met, or
cyclic timing behaviours to implement, a milliscond is OK.

We did consider running the VxWorks tick at 100 us but this was quite
unnecessary!