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Date: Sun, 20 Jun 2010 18:59:37 +0300
From: Andriy Gapon <avg@freebsd.org>
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Cc: Alexander Motin <mav@freebsd.org>
Subject: cpufreq_curr_sysctl: memory allocation
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I noticed that cpufreq_curr_sysctl performs a substantial memory allocation and
deallocation on each call.  Its size is CF_MAX_LEVELS * sizeof(*levels), which
is ~24KB.  This happens even for read-only calls to just query current level.
And such calls happen quite frequently when powerd is running.

I think that this is an unnecessary and avoidable load for VM system.
Couldn't a buffer be preallocated in sc and re-used for the calls?
Even if not, for some reason, then wouldn't it be better to have a dedicated uma
zone for that rather than doing malloc+free?

-- 
Andriy Gapon