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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\u2019m waiting for the purchase of new hardware to go thru, I\u2019m trying to gather more data about the current workload. One of the things I\u2019m trying to do is get a handle on the ratio of reads versus writes for my metadata.</div>
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I\u2019m using \u201cmmdiag \u2014iohist\u201d \u2026 in this case \u201cdm-12\u201d is one of my metadataOnly disks and I\u2019m running this on the primary NSD server for that NSD. I\u2019m 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\u2019m confused as to the difference between \u201cinode\u201d and \u201cmetadata\u201d (I at least _think_ I understand \u201clogData\u201d)?!? The man page for mmdiag doesn\u2019t help and I\u2019ve 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\u2026</div>
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<div class="">Kevin</div>
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