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Date: Mon, 20 Sep 2010 20:35:33 -1000 (HST)
From: Jeff Roberson <jroberson@jroberson.net>
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To: Andriy Gapon <avg@freebsd.org>
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Cc: Andre Oppermann <andre@freebsd.org>, Jeff Roberson <jeff@freebsd.org>,
	Robert Watson <rwatson@freebsd.org>, freebsd-hackers@freebsd.org
Subject: Re: zfs + uma
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On Tue, 21 Sep 2010, Andriy Gapon wrote:

> on 19/09/2010 01:16 Jeff Roberson said the following:
>> Additionally we could make a last ditch flush mechanism that runs on each cpu in
>
> How would you qualify a "last ditch" trigger?
> Would this be called from "standard" vm_lowmem look or would there be some extra
> check for even more severe memory condition?

If lowmem does not make enough progress to improve the condition.

Jeff

>
>> turn and flushes some or all of the buckets in per-cpu caches. Presently that is
>> not done due to synchronization issues.  It can't be done from a central place.
>> It could be done with a callout mechanism or a for loop that binds to each core
>> in succession.
>
> -- 
> Andriy Gapon
>