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-1914 Lustre <p>Update the attached patch from Bug 20943, which adds doxygen comments to the ldlm module, for master.</p> LU-1914

Doxygen comments - ldlm module

Technical task LU-1892 Minor Resolved Fixed Ned Bass Ned Bass documentation Wed, 12 Sep 2012 14:48:42 +0000 Tue, 29 Apr 2014 20:05:17 +0000 Tue, 29 Apr 2014 20:05:17 +0000 Lustre 2.4.0 0 3 <p>I have a few questions about this patch.</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java"> /** - * Hash table <span class="code-keyword">for</span> namespace. + * Resource hash table <span class="code-keyword">for</span> namespace. + * Hash table is organized as an array of \see RES_HASH_SIZE elements. + * Each element is a list_head linking all resources whose name hash is + * equal to the array position. + * \see ldlm_hash_fn <span class="code-keyword">for</span> the actual hash function. */ cfs_list_t *ns_hash; </pre> </div></div> <p>The ldlm namespace resource hashtable now appears to use the generic cfs hash implementation, so I think we can omit any hash table implementation details here.</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java">- /** - * Seconds. - */ + /** + * Seconds. + * Appears to be currently unused. Should be removed. + */ unsigned <span class="code-object">int</span> ns_ctime_age_limit; </pre> </div></div> <p>Contrary to this comment, ns_ctime_age_limit is still used in mdt_handler.c:mdt_getattr_name_lock() (bugzilla 14910). I'm thinking of of a comment along these lines.</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java">/** * <span class="code-object">Number</span> of seconds since the file change time after which the * MDT will <span class="code-keyword">return</span> an UPDATE lock along with a LOOKUP lock. * This allows the client to start caching negative dentries * <span class="code-keyword">for</span> the directory and may save an RPC <span class="code-keyword">for</span> a later stat. */ unsigned <span class="code-object">int</span> ns_ctime_age_limit; </pre> </div></div> <p>But it's still a bit muddled to me. What is the connection between the change time, the update lock, negative dentries, and why does returning an update lock save an RPC for a stat? How is the value chosen? This may not be the right place to explain all these things; perhaps the LDLM_CTIME_AGE_LIMIT definition would be appropriate, and we could provide a reference here. </p> <p><a href="http://review.whamcloud.com/#change,3985" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/#change,3985</a></p> <p>patch landed to master</p> Bugzilla ID 20943.0 Development Rank 1|hzvqbj: Rank (Obsolete) 8140