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To: Ivan Voras <ivoras@fer.hr>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 14 Nov 2006 12:55:57 +0100."
	<ejcasd$2rf$1@sea.gmane.org> 
Date: Tue, 14 Nov 2006 12:03:44 +0000
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Sender: phk@critter.freebsd.dk
Cc: freebsd-arch@freebsd.org
Subject: Re: a proposed callout API 
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In message <ejcasd$2rf$1@sea.gmane.org>, Ivan Voras writes:
>Poul-Henning Kamp wrote:
>
>...
>> 4. We execute all callouts on one CPU only.
>...
>> Short callouts, less than 2 seconds, will be stored in a binary
>> heap (A tree where a node is numerically lower than its parents.)
>> 
>> The depth of the heap is Log2(nodes) and there are very efficient
>> ways to store and access the heap.
>> 
>> Locking will be with one mutex for the heap.
>
>Won't that retain the 1-cpu-only "feature"?

No, that will be one lock per callout-group, however we decide
to use those.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.