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<p class="MsoNormal"><span style="font-size:11.0pt">Just wondering if anyone has any strong views/recommendations with metadata when using GNR code?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I know in “san” based GPFS, there is a recommendation to have data and metadata split with the metadata on SSD.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I’ve also heard that with GNR there isn’t much difference in splitting data and metadata.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">We’re looking at two systems and want to replicate metadata, but not data (mostly) between them, so I’m not really sure how we’d do this without having separate system pool (and then NSDs in different failure
groups)….<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">If we used 8+2P vdisks for metadata only, would we still see no difference in performance compared to mixed (I guess the 8+2P is still spread over a DA so we’d get half the drives in the GNR system active…).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Or should we stick SSD based storage in as well for the metadata pool? (Which brings an interesting question about RAID code related to the recent discussions on mirroring vs RAID5…)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thoughts welcome!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Simon<o:p></o:p></span></p>
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