https://tracker.ceph.com/https://tracker.ceph.com/favicon.ico2020-01-17T09:14:01ZCeph CephFS - Bug #43644: mds: Empty directory check is done on the importer side (at import finish) during migrationhttps://tracker.ceph.com/issues/43644?journal_id=1560692020-01-17T09:14:01ZSidharth Anupkrishnan
<ul><li><strong>Component(FS)</strong> <i>MDS</i> added</li></ul> CephFS - Bug #43644: mds: Empty directory check is done on the importer side (at import finish) during migrationhttps://tracker.ceph.com/issues/43644?journal_id=1560702020-01-17T09:16:00ZSidharth Anupkrishnan
<ul></ul><p>Sidharth Anupkrishnan wrote:</p>
<blockquote>
<p>In the current MDS code, the migration of empty directories is prohibited but it is actually exported during the migration process and a check on the importer side during import_finish() (<a class="external" href="https://github.com/ceph/ceph/blob/master/src/mds/Migrator.cc#L3175">https://github.com/ceph/ceph/blob/master/src/mds/Migrator.cc#L3175</a>) determines whether the directory empty and if so exports it back to the original exporter.</p>
<p>Why is this check not done on the exporter side? We can avoid unnecessary round trips between the exporter and the importing mds.</p>
</blockquote>
<p>Zheng and Patrick. Please take a look</p> CephFS - Bug #43644: mds: Empty directory check is done on the importer side (at import finish) during migrationhttps://tracker.ceph.com/issues/43644?journal_id=1560722020-01-17T12:13:16ZZheng Yanukernel@gmail.com
<ul></ul><p>you are right. we can do the check a export_dir and export_frozen. If directory is empty, abort. But we still need to consider export_pin</p> CephFS - Bug #43644: mds: Empty directory check is done on the importer side (at import finish) during migrationhttps://tracker.ceph.com/issues/43644?journal_id=1560802020-01-17T18:48:45ZPatrick Donnellypdonnell@redhat.com
<ul></ul><p>Zheng Yan wrote:</p>
<blockquote>
<p>you are right. we can do the check a export_dir and export_frozen. If directory is empty, abort. But we still need to consider export_pin</p>
</blockquote>
<p>As I discussed with Sidharth, it appears to me the prohibition on exporting empty directories is just a premature optimization to prevent moving metadata unnecessarily. I think it <em>does</em> make sense for a pinned directory. I'm suggesting we just undo this restriction entirely.</p>
<p>Sidharth, please submit a PR when you have time.</p> CephFS - Bug #43644: mds: Empty directory check is done on the importer side (at import finish) during migrationhttps://tracker.ceph.com/issues/43644?journal_id=1560812020-01-17T18:49:07ZPatrick Donnellypdonnell@redhat.com
<ul><li><strong>Status</strong> changed from <i>New</i> to <i>Triaged</i></li><li><strong>Assignee</strong> set to <i>Sidharth Anupkrishnan</i></li><li><strong>Priority</strong> changed from <i>Normal</i> to <i>Urgent</i></li><li><strong>Target version</strong> set to <i>v15.0.0</i></li><li><strong>Source</strong> set to <i>Development</i></li><li><strong>Backport</strong> set to <i>nautilus</i></li></ul> CephFS - Bug #43644: mds: Empty directory check is done on the importer side (at import finish) during migrationhttps://tracker.ceph.com/issues/43644?journal_id=1566592020-01-23T01:30:06ZPatrick Donnellypdonnell@redhat.com
<ul><li><strong>Status</strong> changed from <i>Triaged</i> to <i>Fix Under Review</i></li><li><strong>Backport</strong> deleted (<del><i>nautilus</i></del>)</li><li><strong>Pull request ID</strong> set to <i>32792</i></li></ul> CephFS - Bug #43644: mds: Empty directory check is done on the importer side (at import finish) during migrationhttps://tracker.ceph.com/issues/43644?journal_id=1596232020-02-26T15:11:11ZPatrick Donnellypdonnell@redhat.com
<ul><li><strong>Status</strong> changed from <i>Fix Under Review</i> to <i>Rejected</i></li></ul>