From owner-freebsd-current  Wed Apr 16 02:00:05 1997
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From: Peter Dufault <dufault@hda.com>
Message-Id: <199704160847.EAA13229@hda.hda.com>
Subject: Extra round robin context switching?
To: current@freebsd.org
Date: Wed, 16 Apr 1997 04:47:26 -0400 (EDT)
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When I added the fixed priority non-round robin scheduling I noticed
I get extra context switching between same-priority processes after
an interrupt/wakeup outside of the explicit "roundrobin" entry.
This happens where wakeup calls "need_resched".  I added logic to
compare priorities before need_resched in my scratchpad version of
kern_synch in ~ftp/dufault/posix4.tgz.

Is this causing extra context switches on heavily loaded systems?

-- 
Peter Dufault (dufault@hda.com)   Realtime Machine Control and Simulation
HD Associates, Inc.               Voice: 508 433 6936