https://jira.whamcloud.com This file is an XML representation of an issue en-us 9.4.14 940014 05-12-2023 https://jira.whamcloud.com/browse/LU-14211 Lustre <p>It should be possible to cleanly interrupt DNE directory migration (e.g. at the end of the current directory) for a long-running recursive directory migration.</p> <p>It would make sense to restructure recursive directory migration as a series of single directory migrations now that this is possible (<a href="https://jira.whamcloud.com/browse/LU-14975" title="DNE3: directory migration in non-recursive mode" class="issue-link" data-issue-key="LU-14975"><del>LU-14975</del></a>). This would provide a number of benefits:</p> <ul class="alternate" type="square"> <li>allow the migration to be interrupted after the current directory has finished</li> <li>allow statistics printing to be done by "<tt>lfs migrate -m</tt>" in userspace after each directory finishes</li> <li>avoid very long-running processes on the MDS</li> <li>simplify restart of directory tree migration</li> <li>allow better (automated) per-directory tuning (stripe count 1/N for small/large directories, select different target MDT by space) as each directory is migrated, instead of using the same parameters for all directories in the tree</li> </ul> LU-14211

DNE3: mechanism to interrupt and resume migration

Improvement Minor Open Unresolved WC Triage Andreas Dilger dne3 Mon, 14 Dec 2020 21:00:25 +0000 Mon, 4 Jul 2022 23:38:32 +0000 0 3 <p>The message "<tt>migration was interrupted, run 'lfs migrate -m %d -c %d -H %s ...' to finish migration</tt>" should also be removed. If the MDS <b>knows</b> the migration options needed to finish the migration of that directory, then it should ignore what the user asked and finish the migration <b>of that directory</b> as originally started. Then, if the user parameters are incompatible with the new directory layout, an second migration should be done on the directory.</p> <p>Running two directory migrations is still faster than having the user try to figure out the right "<tt>lfs migrate -m</tt>" parameters (if they even look at the MDS console log to figure this out), and then run both migrations manually.</p> <p>In addition to commands to stop and resume individual directory migrations, we need to be able to find partially-migrated directories. <del>I've filed <a href="https://jira.whamcloud.com/browse/LU-15990" title="&quot;lfs find&quot; to scan for directory hash flags" class="issue-link" data-issue-key="LU-15990"><del>LU-15990</del></a> to track enhancements to "<tt>lfs find</tt>" to allow finding directories with <tt>migrating</tt> directory hash flag.</del> This was implemented via patch <a href="https://review.whamcloud.com/39340" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/39340</a> "<tt><a href="https://jira.whamcloud.com/browse/LU-11776" title="add &quot;lfs find&quot; support for directory hash flags" class="issue-link" data-issue-key="LU-11776"><del>LU-11776</del></a> utils: add support lfs find with mdt hash flag</tt>".</p> Related LU-14719 LU-14975 LU-15001 LU-14212 LU-11776 LU-15990 Development Rank 1|i01h3b: Rank (Obsolete) 9223372036854775807