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-8209 Lustre <p>It appears that with conversion to clio this important bit of funcionality that allows us to balance lock counts on clients was lost.</p> <p>Vitaly tracked it to this patch:</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java">commit fd908da92ccd9aab4ffc3d2463301831260c0474 Author: huanghua &lt;huanghua&gt; Date: Thu Feb 7 08:07:16 2008 +0000 b=14149 i=yong.fan i=rahul.deshmukh i=nikita.danilov - use req_capsule <span class="code-keyword">interface</span> <span class="code-keyword">for</span> client. - add some interoperability support on server side. </pre> </div></div> <p>The removal seems to be accidental.<br/> Where before all enqueues came via a single path and ELC was alwas engaged, this is no longer the case.<br/> The patch was cli_enqueue() -&gt; ldlm_prep_enqueue_req()<br/> and this call to ldlm_prep_enqueue_req() is now missing for glimpse enqueue.</p> LU-8209

glimpse lock request does not engage ELC to drop unneeded locks

Bug Major Resolved Fixed Hongchao Zhang Oleg Drokin Thu, 26 May 2016 23:41:46 +0000 Fri, 21 Dec 2018 18:07:22 +0000 Sat, 8 Oct 2016 19:11:48 +0000 Lustre 2.9.0 0 10 <p>Well, if I correctly understand, this means that presently in current master, ldlm_cli_enqueue() does not call ldlm_prep_<span class="error">&#91;enqueue,elc&#93;</span>_req() but this is left to upper layer/callers responsibility to track for/submit eligible locks, right?</p> <p>Based on this now, my understanding is that :<br/> _ Client glimpse enqueue seems to start with cl_glimpse_lock(), calling cl_lock_request() with CEF_ASYNC flag set in cl_lock_descr struct. CEF_MUST flag is also set to ensure lock request will be issued and not be considered as lock-less.<br/> _ cl_lock_request() will first call cl_lock_init()<br/> _ cl_lock_init() will call ::coo_lock_init method() for each layer<br/> _ thus osc_lock_init() will be called and will set LDLM_FL_HAS_INTENT flag due to CEF_ASYNC present (with help from osc_enq2ldlm_flags()), and will also set ols_glimpse bit<br/> _ back in cl_lock _request(), it will then call cl_lock_enqueue()<br/> _ cl_lock_enqueue() will call ::clo_enqueue() method for each layer, and thus osc_lock_enqueue() will be called<br/> _ osc_lock_enqueue() will call osc_enqueue_base(), because ols_glimpse bit and not lock-less<br/> _ osc_enqueue_base() will call ldlm_prep_enqueue_req() because of LDLM_FL_HAS_INTENT is set</p> <p>What do you think? Did I miss something there ?</p> <p>err... the opposite. the glimpse works fine. others are not, because of:</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>@@ -646,7 +650,10 @@ int ldlm_cli_enqueue(struct obd_export *exp, struct ptlrpc_request **reqp, /* lock not sent to server yet */ if (reqp == NULL || *reqp == NULL) { - req = ldlm_prep_enqueue_req(exp, 2, size, NULL, 0); + req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp), + &amp;RQF_LDLM_ENQUEUE, + LUSTRE_DLM_VERSION, + LDLM_ENQUEUE); if (req == NULL) { failed_lock_cleanup(ns, lock, lockh, einfo-&gt;ei_mode); LDLM_LOCK_PUT(lock); </pre> </div></div> <p>Hongchao Zhang (hongchao.zhang@intel.com) uploaded a new patch: <a href="http://review.whamcloud.com/21739" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/21739</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-8209" title="glimpse lock request does not engage ELC to drop unneeded locks" class="issue-link" data-issue-key="LU-8209"><del>LU-8209</del></a> ldlm: engage ELC for all ldlm enqueue req<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: 1<br/> Commit: ab97c207d6310426d6872d2fa234ad4ed5dfeebb</p> <p>Oleg Drokin (oleg.drokin@intel.com) merged in patch <a href="http://review.whamcloud.com/21739/" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/21739/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-8209" title="glimpse lock request does not engage ELC to drop unneeded locks" class="issue-link" data-issue-key="LU-8209"><del>LU-8209</del></a> ldlm: engage ELC for all ldlm enqueue req<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: <br/> Commit: e8f5f496ed41f237c4fb44cc7355f1ded4c33ac6</p> <p>Landed for 2.9</p> Related LU-6529 Development Rank 1|hzycy7: Rank (Obsolete) 9223372036854775807 Severity