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Date: Tue, 21 Sep 2010 12:51:59 +0300
From: Andriy Gapon <avg@freebsd.org>
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To: Steven Hartland <killing@multiplay.co.uk>
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Cc: freebsd-fs@freebsd.org
Subject: Re: zfs very poor performance compared to ufs due to lack of cache?
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on 21/09/2010 12:49 Andriy Gapon said the following:
> on 21/09/2010 12:27 Steven Hartland said the following:
>> forces into Inact and ARC never seems to push back to balance this out :(
> 
> Just a general note here.
> ARC is not designed to "push back".  It's designed to give up memory under
> pressure, it's designed to expand into free space, it's not designed to create
> the pressure.
> Incorrect language produces incorrect perception resulting in incorrect
> expectations.
> 

I guess what I wanted to say is - why do you want ARC to grow more in this case?
When you know that the data that sendfile uses is in those Inactive pages.

-- 
Andriy Gapon