Messages in this thread | | | Date | Thu, 28 Apr 2005 10:19:15 -0700 | From | Joel Becker <> | Subject | Re: [PATCH 1a/7] dlm: core locking |
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On Thu, Apr 28, 2005 at 02:48:57PM +0100, Stephen C. Tweedie wrote: > reduce the latency for this case. My gut feeling, though, is that I'd > still prefer to see the DLM doing its work properly, cluster-wide in > this case, as precaution against accidents if we get inconsistent states > on disk leading to two nodes trying to create the same lock at once. > Experience suggests that such things *do* go wrong, and it's as well to > plan for them --- early detection is good!
And unacceptably slow. With LKM_LOCAL, OCFS2 approaches ext3 speed untarring a kernel tree, because everything under the toplevel directory is a candidate for LKM_LOCAL. Network communication may be fast, but pagecache operations are even faster. I don't know by how much, but I bet if we turned off LKM_LOCAL in the OCFS2 DLM, we'd lose a lot of speed.
Joel
--
One look at the From: understanding has blossomed .procmailrc grows - Alexander Viro
Joel Becker Senior Member of Technical Staff Oracle E-mail: joel.becker@oracle.com Phone: (650) 506-8127
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