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<p class="MsoNormal">Greetings!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">During the helpful LUG tutorial from Rick Mohr on advanced lustre file layouts, it was mentioned that “lfs mirror” could be used to improve read performance. And the manual supports this, stating “files that are concurrently read by many
clients (e.g. input decks, shared libraries, or executables) the aggregate parallel read performance of a single file can be improved by creating multiple mirrors of the file data”.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What method does Lustre use to ensure that multiple clients balance their read workloads from the multiple mirrors? Are there any tuning parameters that should be considered, other than making sure the “preferred” flag is NOT set on a
single mirror, to help even out the read workload among the OSTs?<o:p></o:p></p>
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<p class="MsoNormal">Has anyone tested this and quantified the performance improvement?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Nathan<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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