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<p>We were running 2.5.3.90 with changelogs enabled earlier this summer. We ran into a catalog corruption issue (<span class="quote">LU-6556) - we decided to deregister our changelog users, move the
</span>CONFIGS/changelog_{catalog,users} files out of the way, and carry on until we had an opportunity to upgrade. We did not remove anything from /O/1/d* at that time (though we probably should have).<br>
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<p>We've observed that mounting our MDT can take several-to-many minutes - I can see with iostat that the MDT is very busy with reads while it is being mounted. I suspect that those stale files in /O/1/d* are the reason (there are lots of them), as they are
processed by the OSP sync at MDT startup. I looked with debugfs at the /O/1/d* directories - there are 1000s of files and their timestamps are consistent with when we were using changelogs. I dumped a few randomly selected ones and checked with llog_reader
that the types of records they contain are CHANGELOG_REC (type=10660000). <br>
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<p>At the least, I think we should to remove the files in /O/1/d* that contain CHANGELOG_REC entries. Can I just delete every file in /O/1/d*, or do I need to be careful and only remove the CHANGELOG_REC entries?
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<p>The reason I ask is that I do see a handful of files that are not changelog-related in these directories - their timestamps are newer and their record type as reported by llog_reader is not CHANGELOG_REC or CHANGELOG_USER. There are only a small number
of such files, though.</p>
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<p>Thanks,</p>
<p>Craig Prescott</p>
University of Florida Research Computing
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