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From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Miroslav Lachman <000.fbsd@quip.cz>
Subject: Re: RHEL to FreeBSD file server
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On Tue, 13 Nov 2012, Miroslav Lachman wrote:

> Jason Keltz wrote:
>> Thanks for your reply Bob!  I've thought about adding more memory to the
>> R720 which can go up to 768 GB. I'm just not quite sure how much we
>> need, but it can never hurt to add more, I guess. I know you can never
>> have too much memory!! :)
>
> Yes you can:
>
> http://www.zfsbuild.com/2012/03/02/when-is-enough-memory-too-much/
> http://www.zfsbuild.com/2012/03/05/when-is-enough-memory-too-much-part-2/
>
> I don't know if the same problem exists on FreeBSD or not.

The Solaris kernel and ZFS have a fairly intimate relationship 
regarding memory and ZFS is able to give up memory to the kernel on 
demand.  FreeBSD does not have this intimate relationship. 
Regardless, code specific to ZFS likely behaves similarly.  The 
behavior of semaphoring depends on CPU architecture and how many CPU 
cores are in the system.

Bob
-- 
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/