luse vs. lun

[mark_720]

Guys,
I can't figure out which would be better. Cannot find info. on net.
I have been presented with 86 luns at 13.5 GB each. The San manager claims that I will get better performance from the xp without using luse 3 rather than concatinating. Please explain why this is. I would appreciate any help here.

Mark
Independence Blue Cross

[Pedro Cirne]

Hi Mark,

I would prefere to concatenate those luns, depending on the number/size of VG you're going to create. It gives some more work to your SAN admin, but will be easier to administrate in the future.

With 86 luns (plus alternate paths, I guess) you'll have 172 devices to manage!

Enjoy :)

Pedro

[Mel Burslan]

Mark,

I don't know the technicality but your Open-E LUN size has some importance as far as the efficient operation of disk controllers on your XP array. This is what we were told by the HP Technical team, who visited us at the time of implementation and advised to stick to the OPEN-E LUNS as we grow our environment. We have SAP on oracle database running on much larger number of LUNs and we do not hear a performance problem so far. Yes, at the time of mount/unmount/fsck, you have to deal with a lot of stuff, but, performance wise, LUSE is not the way to go as far as my limited san knowledge goes. LUSE is the last resort to gather up otherwise unusable chunks of space, leftover on the disk groups and present then as usable disk space, where performance is not a big concern.

If I were you, I would stick to OPEN-E LUNs instead of LUSE.

My 2 cents...

[Sheriff Andy]

If you stripe the luns in a volume group, then there would be a much better performance (more disks writing simultaniously). Otherwise I don't feel that you are gaining anything.

Andy