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From: Erich Focht <efocht@ess.nec.de>
To: Ingo Molnar <mingo@elte.hu>
Subject: Re: O(1) scheduler "complex" macros
Date: Thu, 11 Jul 2002 11:25:26 +0200
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Ingo,

the last fix survived one night of testing with included udelay(100), so
I would consider it stable. Thanks again!

The performance with the new "complex" macros is as expected worse than
with the simple ones, we see 10% in some cases, which is hurting a lot.
Would you please consider moving the location of the switch_lock from
the end of the task_struct to the hot area near the scheduler related
variables? The effect may vary depending on the cache line size but
having it behind *array or sleep_timestamp would probably save us a cache
miss here.

Regards,
Erich

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