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-14756 Lustre <p>Today, all LDLM locks created by lockahead are cached after use.  In many situations, this is not desirable - The application or library using them only expects to use them once.</p> <p>The main negative side effect of this caching is that the locks pile up, and then may all need to be flushed rapidly, such as when a file is deleted, or if data is ready from a different node where it was written.  This can induce significant delays.</p> <p>It would be much better to create the option of locks which remain in cache until used once, then do not <b>return</b> to cache.  This can be done fairly easily with a new LDLM flag, accessible via the flags on ladvise requests.</p> LU-14756

Single use LDLM locks for lockahed

Improvement Minor Open Unresolved Patrick Farrell Patrick Farrell Thu, 10 Jun 2021 19:17:05 +0000 Thu, 10 Jun 2021 23:24:43 +0000 0 3 <p>Patrick Farrell (farr0186@gmail.com) uploaded a new patch: <a href="https://review.whamcloud.com/43975" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/43975</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-14756" title="Single use LDLM locks for lockahed" class="issue-link" data-issue-key="LU-14756">LU-14756</a> llite: Add cache once to lockahead<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: 1<br/> Commit: 1126653130c43926f5bfb07a9323a7d2028d206a</p> <p>This is a generic improvement to lockahead, but this also has some potential applications for some ideas I have for improving unusual i/o patterns.  Those ideas may never actually happen, but this improvement is relatively simple &amp; should be beneficial to users of lockahead, so it's still worth having.</p> Development Rank 1|i01wqn: Rank (Obsolete) 9223372036854775807