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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: can someone help me with this code (explanation)
Date: Fri, 26 Sep 2014 18:23:26 +0200
Organization: cbb software GmbH
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Date: 2014-09-26T18:23:26+02:00
List-Id: <comp.lang.ada>

On Fri, 26 Sep 2014 17:31:45 +0200, Björn Lundin wrote:

> On 2014-09-26 16:49, J-P. Rosen wrote:
>> Le 26/09/2014 16:15, Björn Lundin a écrit :
>>> http://www.sigada.org/conf/sa98/papers/mueller.pdf
>>>
>>> I did not read all of it, but the conclusion is that
>>> context switches are bad for performance.
>>> If a protected object can REPLACE a task, it
>>> will show in measurements. (and they did measure)
>> 
>> That's a paper from 16 years ago. Computers as well as compilers have
>> evolved a lot, therefore I would not trust the paper for making a
>> decision nowadays...
> 
> Yes, I did point that out.
> But still, I have no problem believing
> that context switches still is bad for performance.

Undoubtedly so. But on a multi-core architecture there might be no context
switch needed. In that case rendezvous might become as fast as a call to a
protected object's entry.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de