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From: Lutz Donnerhacke <lutz@iks-jena.de>
Newsgroups: comp.lang.ada
Subject: Re: High CPU in tasking
Date: Mon, 28 Jun 2004 08:17:49 +0000 (UTC)
Organization: IKS GmbH Jena
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* Wojtek Narczynski wrote:
>> Debugging turned out:
>>   - Every writing to the ringbuffer wakes up all reader tasks.
>
> This sounds like the "thundering herd" problem linux used to have with
> acccept call. This has been fixed, so maybe in this case the problem
> should be reported and eventually fixed, or is it required to wake em
> all for some reason?

No, there is no "thundering herd" problem. Because written data is processed
by all reader tasks, every waked task has work to do.

I only point to the ARM requried behavior of a protected task.