From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Zhuravlev Date: Mon, 16 Feb 2009 18:26:31 +0300 Subject: [Lustre-devel] Some investigations on MDS creation rate In-Reply-To: References: Message-ID: <499985A7.7000600@sun.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org Oleg Drokin wrote: > I also performed tests on HEAD and it performs significantly worse > (5.8k at most). Even with all the same fixes ported from b1_6. > The CPU remains the same and I used lock meter to verify that there > is no significant lock contention. > Looking into the oprofile results, it looks like all code just > became slower (judging by more hits in various areas for the same > workload). > Also some parts of the code are now more heavily loaded (ptlrpc > +ldlm in HEAD draws more cpu time, llite portion of the code is 50% > more time notice HEAD takes two ldlm locks for each create, 1.6 takes one. > I have no idea why the variability and I do not see anything very > obvious that would explain sudden overall performance degradation of > HEAD code either yet. it would be interesting to gather L1/L2 cache hit/miss with oprofile for 1.6 and HEAD. thanks, Alex