<div dir="ltr"><div class="gmail_extra"><div><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div>Thanks, </div><div><br></div><div>I suppose what I'm trying to gain is some clarity on what choice is best for a given application. How do I know if it's better for me to use a raid card or not, to include flash-cache on it or not, to use ZFS or not, when combined with a small number of SSDs in Replica 3. </div><div><br></div><div><br></div></div></div></div></div></div></div></div></div>
<br><div class="gmail_quote">On Mon, Apr 9, 2018 at 10:49 AM, Alex Crow <span dir="ltr"><<a href="mailto:acrow@integrafin.co.uk" target="_blank">acrow@integrafin.co.uk</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF"><span class="">
On 09/04/18 16:49, Vincent Royer wrote:<br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div><br>
</div>
<div>Is a flash-backed Raid required for JBOD, and
should it be 1gb, 2, or 4gb flash?<br>
</div>
</div>
</blockquote>
<br>
</div>
</div>
</div>
</blockquote></span>
RAID and JBOD are completely different things. JBODs are just that,
bunches of disks, and they don't have any cache above them in
hardware. If you're going to use ZFS under Gluster, look at the ZFS
docs first. Short answer is no. If Gluster passes sync writes down
to the lower level FS as sync, and you decide to use a ZFS SLOG
device, usually an SSD, it should have power fail protection
capacitors.<br>
<br>
Do *not* use a RAID controller for ZFS, use a decent HBA instead, so
ZFS can access the disks directly. Using a RAID controller is not
only wasteful it's setting yourself up for a world of pain when a
ZFS VDEV member device fails. Don't do it.<br>
<br>
<br><pre>--
This message is intended only for the addressee and may contain
confidential information. Unless you are that person, you may not
disclose its contents or use it in any way and are requested to delete
the message along with any attachments and notify us immediately.
This email is not intended to, nor should it be taken to, constitute advice.
The information provided is correct to our knowledge & belief and must not
be used as a substitute for obtaining tax, regulatory, investment, legal or
any other appropriate advice.
"Transact" is operated by Integrated Financial Arrangements Ltd.
29 Clement's Lane, London EC4N 7AE. Tel: (020) 7608 4900 Fax: (020) 7608 5300.
(Registered office: as above; Registered in England and Wales under
number: 3727592). Authorised and regulated by the Financial Conduct
Authority (entered on the Financial Services Register; no. 190856).
</pre><br>
</div>
<br>______________________________<wbr>_________________<br>
Gluster-users mailing list<br>
<a href="mailto:Gluster-users@gluster.org">Gluster-users@gluster.org</a><br>
<a href="http://lists.gluster.org/mailman/listinfo/gluster-users" rel="noreferrer" target="_blank">http://lists.gluster.org/<wbr>mailman/listinfo/gluster-users</a><br></blockquote></div><br></div></div>