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Date: Mon, 15 Feb 2010 10:49:47 +0200
Message-ID: <cf9b1ee01002150049o43fced71ucb5776a0a1eaf4cf@mail.gmail.com>
From: Dan Naumov <dan.naumov@gmail.com>
To: FreeBSD-STABLE Mailing List <freebsd-stable@freebsd.org>
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Subject: RE: hardware for home use large storage
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> I had a feeling someone would bring up L2ARC/cache devices.  This gives
> me the opportunity to ask something that's been on my mind for quite
> some time now:
>
> Aside from the capacity different (e.g. 40GB vs. 1GB), is there a
> benefit to using a dedicated RAM disk (e.g. md(4)) to a pool for
> L2ARC/cache?  The ZFS documentation explicitly states that cache
> device content is considered volatile.

Using a ramdisk as an L2ARC vdev doesn't make any sense at all. If you
have RAM to spare, it should be used by regular ARC.


- Sincerely,
Dan Naumov