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From: John Baldwin <jhb@freebsd.org>
To: freebsd-hackers@freebsd.org
Subject: Re: why no per-thread scheduling niceness?
Date: Tue, 26 Feb 2013 15:30:37 -0500
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Cc: Ian Lepore <ian@freebsd.org>
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On Friday, February 22, 2013 2:12:54 pm Ian Lepore wrote:
> I'm curious why the concept of scheduling niceness applies only to an
> entire process, and it's not possible to have nice threads within a
> process.  Is there any fundamental reason why it couldn't be supported
> with some extra bookkeeping to track niceness per thread?

Only that the existing 'nice' command only works on processes and nice is 
traditionally a process concept.  Also see things like renice.  Individual 
threads can already alter their priority somewhat (e.g. to set an individual 
thread to an idle or real-time priority).

-- 
John Baldwin