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Date: Thu, 10 Jan 2002 13:57:58 -0800
From: Mike Kravetz <kravetz@us.ibm.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@transmeta.com>, linux-kernel@vger.kernel.org,
        Anton Blanchard <anton@samba.org>, george anzinger <george@mvista.com>,
        Davide Libenzi <davidel@xmailserver.org>,
        Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [patch] O(1) scheduler, -G1, 2.5.2-pre10, 2.4.17 (fwd)
Message-ID: <20020110135758.C15171@w-mikek2.des.beaverton.ibm.com>
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If I run 3 cpu-hog tasks on a 2 CPU system, then 1 task will get an
entire CPU while the other 2 tasks share the other CPU (easily verified
by a simple test program).  On previous versions of the scheduler
'balancing' this load was achieved by the global nature of time slices.
No task was given a new time slice until the time slices of all runnable
tasks had expired.  In the current scheduler, the decision to replenish
time slices is made at a local (pre-CPU) level.  I assume the load
balancing code should take care of the above workload?  OR is this the
behavior we desire?  We certainly have optimal cache use.

-- 
Mike
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