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Subject: Re: One Priority Per Run Queue
To: Warner Losh <imp@bsdimp.com>,
 "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>
References: <1aafd6a2-828c-06f5-bdac-e4c953a403b5@FreeBSD.org>
 <CANCZdfogvSXzHT33JxzvZ+0h8BjRetM=-vkPjzhyNJgznPhAnQ@mail.gmail.com>
From: Eric van Gyzen <vangyzen@FreeBSD.org>
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Date: Fri, 31 Mar 2017 20:05:43 -0500
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On 03/29/2017 16:18, Warner Losh wrote:
> How does this scheme prevent starvation of low priority processes? Or
> rather, how will this change after this change.

I don't know.  How does the current scheme do this?

I had thought the rationale for assigning four priorities to each run queue was
that it was "good enough" and the smaller number of run queues reduced the
overhead of the scheduler.  Is there a more interesting reason that I'm missing?
 (This wouldn't be the first time.)

Cheers,

Eric