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How are you measuring write speed?<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> lustre-discuss <lustre-discuss-bounces@lists.lustre.org> on behalf of Zeeshan Ali Shah <javaclinic@gmail.com><br>
<b>Sent:</b> Tuesday, August 28, 2018 1:30:03 AM<br>
<b>To:</b> lustre-discuss@lists.lustre.org<br>
<b>Subject:</b> [lustre-discuss] separate SSD only filesystem including HDD</font>
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<div dir="ltr">Dear All, I recently deployed 10PB+ Lustre solution which is working fine. Recently for genomic pipeline we acquired another racks with dedicated compute nodes with single 24-NVME SSD Servers/Rack . Each SSD server connected to Compute Node
via 100 G Omnipath.
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<div>Issue 1: is that when I combined SSDs in stripe mode using zfs we are not linearly scaling in terms of performance . for e..g single SSD write speed is 1.3GB/sec , adding 5 of those in stripe mode should give us atleast 1.3x5 or less , but we still get
1.3 GB out of those 5 SSD .</div>
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<div>Issue 2: if we resolve issue #1, 2nd challenge is to allow 24 NVMEs to compute nodes distributed and parallel wise , NFS not an option .. tried glusterfs but due to its DHT it is slow.. </div>
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<div>I am thinking to add another Filesystem to our existing MDT and install OSTs/OSS over the NVME server.. mounting this specific ssd where needed. so basically we will end up having two filesystem (one with normal 10PB+ and 2nd with SSD).. </div>
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Does this sounds correct ? </div>
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<div>any other advice please ..</div>
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<div>/Zeeshan</div>
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