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<span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">From:
</b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class=""><a href="mailto:gpfsug-discuss-owner@spectrumscale.org" class="">gpfsug-discuss-owner@spectrumscale.org</a><br class="">
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<span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">Subject:
</b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class=""><b class="">Re: [gpfsug-discuss] RAID type for system pool</b><br class="">
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<span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">Date:
</b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class="">September 10, 2018 at 11:35:05 AM CDT<br class="">
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<span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b class="">To:
</b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;" class=""><a href="mailto:klb@accre.vanderbilt.edu" class="">klb@accre.vanderbilt.edu</a><br class="">
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<div class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Hi
All,</span>
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So while I’m waiting for the purchase of new hardware to go thru, I’m trying to gather more data about the current workload. One of the things I’m trying to do is get a handle on the ratio of reads versus writes for my metadata.</div>
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I’m using “mmdiag —iohist” … in this case “dm-12” is one of my metadataOnly disks and I’m running this on the primary NSD server for that NSD. I’m seeing output like:</div>
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<div class="">11:22:13.931117 W inode 4:299844163 1 0.448 srv dm-12 <redacted></div>
<div class="">11:22:13.932344 R metadata 4:36659676 4 0.307 srv dm-12 <redacted></div>
<div class="">11:22:13.932005 W logData 4:49676176 1 0.726 srv dm-12 <redacted> </div>
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<div class="">And I’m confused as to the difference between “inode” and “metadata” (I at least _think_ I understand “logData”)?!? The man page for mmdiag doesn’t help and I’ve not found anything useful yet in my Googling.</div>
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<div class="">This is on a filesystem that currently uses 512 byte inodes, if that matters. Thanks…</div>
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<div class="">Kevin</div>
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