True. The only point I would like to add is that you are using a 2+ yr old version of the fs. You should upgrade to atleast SLES9 SP4.
Luis Freitas wrote: > Karim, > > This is not OCFS2 related, it is more related to the disk hardware > capabilities and how it works. > > That will depend on your OS, HBAs and storage, and the workload. > > There is a maximum queue depth associated with each LUN, so if you use > several LUNs on the same device, you could achieve more outstanding scsi > commands open on the controller. But each port will also have a maximum queue > depth that cannot be excedeed, so at some point using extra LUNs wont give > you this advantage. > > If the storage/disk have more outstanding requests it could provide a > better performance by reordering them to provide a larger overall throughput, > given that the storage hardware supports this. Probably it supports it, since > even low end SATA disks supports reordering nowadays. > > On the other hand the database (Or ASM for that matter) has no ideia that > these luns are from the same device, so it will spread the data evenly > accross them, and your data will end up scattered accross the disk, instead > of concentrated at the start of the disks. This will bring a performance > penalty, most noticeable on full table scan operations since they read the > data sequentially from the start to the end. If you tune the tables extent > size you can work around this problem. > > Regards, > Luis > > --- On Thu, 12/18/08, Karim Alkhayer <[email protected]> wrote: > >> From: Karim Alkhayer <[email protected]> >> Subject: [Ocfs2-users] Filesystem Block Size w// DB_BLOCK_SIZE >> To: [email protected] >> Date: Thursday, December 18, 2008, 9:20 PM >> Hello All, >> >> We're hosting DB1 and DB2 with db_block_size set to >> 8K, 16K respectively >> >> File system creation is done with mkfs.ocfs2 -b 4K -C 32K >> -N 4 -L LABLE >> /dev/mapper/xxxx >> >> Mount is done with: ocfs2 _netdev,datavolume,nointr 0 0 >> >> I'd like to know if we can separate most of the >> tablespaces on different >> LUNs, even if they're on the same disk group sometimes, >> is it possible to >> gain better performance? Is the impact limited to the time >> of creating the >> tablespaces only (assuming they're pre-sized properly)? >> >> Current OCFS2 version is 1.2.1 >> >> Current OCFS2 components: >> ocfs2-tools-1.1.4-0.5 >> ocfs2console-1.1.4-0.5 >> >> # uname -r >> Kernel 2.6.5-7.257-default >> >> # cat /etc/SuSE-release >> SUSE LINUX Enterprise Server 9 (ia64) VERSION = 9 >> PATCHLEVEL = 3 >> >> Oracle 10.1.0.5 >> >> Appreciate your input >> >> Best regards, >> >> Karim >> _______________________________________________ Ocfs2-users mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-users
