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<span style="text-transform: none;">Dear LQCD JLab compute and storage users,</span></div>
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As we get ready to deploy a new 4PB Lustre-filesystem based storage hardware we need to address the topic of migrating
<u>existing data with small files</u> from /volatile and /cache storage areas to the new filesystem. Small files are a performance killer for the Lustre filesystem and will slow down the data migration process and so we would like to take the opportunity to
bring this to your attention.</div>
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Small files are defined as files that have sizes less than 1MB.</div>
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As of now we plan to <u>not migrate any small files</u> to the new storage system. To mitigate this, we encourage everyone to please do the following:</div>
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<div role="presentation" style="direction: ltr;"><span style="text-transform: none;">Check your group/project small file count in /volatile and /cache using this following web pages ->
</span><span style="color: rgb(0, 120, 212); text-transform: none;"><a href="https://lqcd.jlab.org/lqcd/volatileDisk/project" title="https://lqcd.jlab.org/lqcd/volatileDisk/project" data-outlook-id="a0d1e037-d517-49fb-86e7-76e527be15a1" style="color: rgb(0, 120, 212);">link
to volatile</a></span><span style="text-transform: none;">, </span><span style="color: rgb(0, 120, 212); text-transform: none;"><a href="https://lqcd.jlab.org/lqcd/cacheDisk/project" title="https://lqcd.jlab.org/lqcd/cacheDisk/project" data-outlook-id="bf7cf255-2321-4d5f-bf41-79febda97ae7" style="color: rgb(0, 120, 212);">link
to cache</a></span></div>
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<div role="presentation" style="direction: ltr;"><span style="text-transform: none;">Do the following to reduce your small file count:</span></div>
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<div role="presentation"><span style="text-transform: none;">delete files that are no longer needed -OR-</span></div>
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<div role="presentation"><span style="text-transform: none;">compress small files into a single file -OR -</span></div>
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<div role="presentation"><span style="text-transform: none;">move small files to /work.</span></div>
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<span style="text-transform: none;">If you have any questions or concerns, please do not hesitate to email me directly.</span></div>
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<p style="margin: 0in; font-family: Calibri, sans-serif;"><span style="font-family: Arial, Arial, Helvetica, sans-serif; font-size: 11pt; color: black;">Amitoj Singh</span><span style="font-family: Arial, Arial, Helvetica, sans-serif; font-size: 11pt; color: rgb(33, 33, 33);">, </span></p>
<p style="margin: 0in; font-family: Calibri, sans-serif;"><span style="font-family: Arial, Arial, Helvetica, sans-serif; font-size: 11pt; color: rgb(33, 33, 33);">HPC Architect</span></p>
<p style="margin: 0in; font-family: Calibri, sans-serif;"><span style="font-family: Arial, Arial, Helvetica, sans-serif; font-size: 11pt; color: rgb(33, 33, 33);">High Performance Data Facility</span></p>
<p style="margin: 0in;"><span style="font-family: Arial, Arial, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);">Computational Sciences and Technology Division</span></p>
<p style="margin: 0in; font-family: Calibri, sans-serif;"><span style="font-family: Arial, Arial, Helvetica, sans-serif; font-size: 11pt; color: rgb(33, 33, 33);">Thomas Jefferson National Accelerator Facility</span></p>
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