Red Hat Bugzilla – Bug 151815
Backup/Restore are very slow on OCFS with 2.4.21-20.ELsmp
Last modified: 2007-11-30 17:07:06 EST
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Description of problem:
I am using Redhat AS 3.0 (Update 3) with "2.4.21-20.ELsmp" Kernel with a 2 node RAC running OCFS (ocfs-2.4.21-EL-smp-1.0.13-1).Shared disks reside on a HP MA8000 SAN and are connected to the server using QLogic 2340 HBAs.Every server has only one HBA.Before upgrading to Kernel 2.4.21-20.ELsmp I was getting decent performace with tape backups and restores which is done over the network using HP Data Protector 5.but after the upgrade the performance of backups/restores have degraded considerabley.One intresting thing I noted was that when the backup is running and if I start a dd read process on the other shared file system in the same server, the backup speed picks up almost 2-3 times.But doing the same with restore doesn't help at all.
Is there any bug with kernel 2.4.21-20.ELsmp which is causing this behavior?
Version-Release number of selected component (if applicable):
Kernel 2.4.21-20 was RHEL3-U3 and that kernel had a bug in which inodes were not
preperly reclaimed. That bug was fixed in RHEL3-U4/kernel-2.4.21-27, can you
grab that kernel or even the latedt RHEL3-U5 kernel and see if the problem you
described is fixed?
Thank You, Larry Woodman
I installed "2.4.21-27.0.2.ELsmp" kernel and ran the backups again but
still the same result. By running a "dd read" process on another filesystem
which is using a separate disks (LUN) makes the backup to run almost 10 times
At this point I think we need to have Oracle look at this sice its OCFS and from
what I can tell its not happening on other file systems.
I did a test by creating a EXT3 filesystem on the same disks.The backup
speed was fine but the restore to the same disks using the same backup was
Can there be a bug in the drive of Qlogic card?