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<p>Dear All,</p>
<p>I have a related question. The documentation says nothing about
the recommended recordsize for MDTs with ZFS backend. Are there
any recommendation? Or is data on MDTs stored in a way that the
recordsize does not matter?</p>
<p>Thanks,<br>
Robert<br>
</p>
<br>
<div class="moz-cite-prefix">On 09/28/2018 12:54 AM, Andreas Dilger
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:21460AC3-8004-4A59-AB80-38AAB1CC530B@whamcloud.com">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Firstly, we don't test anything larger than 1MB.
<div><br>
</div>
<div>Secondly, the best recordsize is up to the apication IO
pattern. If it is streaming writes, it might be OK. If it is
random write then probably not. <br>
<br>
<div id="AppleMailSignature">Cheers, Andreas</div>
<div><br>
On Sep 27, 2018, at 19:04, Riccardo Veraldi <<a
href="mailto:Riccardo.Veraldi@cnaf.infn.it"
moz-do-not-send="true">Riccardo.Veraldi@cnaf.infn.it</a>>
wrote:<br>
<br>
</div>
<blockquote type="cite">
<div>
<p>Hello,</p>
<p>I have always been using ZFS record size to 1MB with
Lustre on top of ZFS. Anyway it is possible to set it to
more than 1MB. May this have any benefit in performance
and is it recommended to set for example:</p>
<div class="code">
<pre>echo 4194304 > /sys/module/zfs/parameters/zfs_max_recordsize</pre>
</div>
<pre>zfs set recordsize=4m zpool
</pre>
<p>Thank you.</p>
<p>Rick</p>
<p><br>
</p>
</div>
</blockquote>
<blockquote type="cite">
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