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Date: Wed, 18 Sep 2013 21:47:33 -0700
Message-ID: <CAN0CFw2L52jSyarbzqPAbD_vNUmg48xfV7hAZo79+U4HN3CZ+w@mail.gmail.com>
Subject: Re: [gentoo-user] ZFS
From: Grant <emailgrant@gmail.com>
To: Gentoo mailing list <gentoo-user@lists.gentoo.org>
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>>> turn off readahead. ZFS' own readahead and the kernel's clash - badly.
>>> Turn off kernel's readahead for a visible performance boon.
>> You are probably not talking about ZFS readahead but about the ARC.
>
> which does prefetching. So yes.

I'm taking notes on this so I want to clarify, when using ZFS,
readahead in the kernel should be disabled by using blockdev to set it
to 8?

- Grant