VMware Cloud Community
clayinatl
Enthusiast
Enthusiast

question about lun best practices for virtualized storage - compellent

since all the storage is virtualized at a block level on our fc compellent sans, does it make any sense to have smaller luns?  currently most of our luns are about 300GB and we have about 120 luns mapped to our 21 node cluster (all 4.1 esx).  i would propose to go with about 2/3 less luns and just increase the size.    my thoughts are we would see some better performance with less luns.  thoughts about that?

Tags (4)
Reply
0 Kudos
3 Replies
depping
Leadership
Leadership

300GB is fairly small and considering the overhead you would have with a rescan for instance I think going to larger size volumes would not hurt. In the end it all depends where the blocks are located so I guess you will not see much difference.

Duncan (VCDX)

Available now on Amazon: vSphere 4.1 HA and DRS technical deepdive

Reply
0 Kudos
fatihsolen
Contributor
Contributor

We are using on our prod. enviroment "Compellent Storage" and our all of LUNs are 500 GB (We have just 12 LUNs)

~2 years ago we decided that after our tests. It gave the best results for our environments.

And i agree with depping

Blog (Turkish) | www.fatihsolen.com
Reply
0 Kudos
nabeelsayegh
Contributor
Contributor

You can certainly go larger than 300GB LUN's. We use a combination of 500GB LUN (from RAID 10 pools) and 1TB LUN's (from SATA) pools. We allocate storage to our VM's from each pool depending on what the vmdk will be used for. There are (under the cover) benefits that happen at the ESX layer when ou use multiple LUN's.  The upper capacity limit is 2TB's so it is really going to be how you use your system and if you start seeing that the larger LUNs are getting overrun wit IOPS (either at the ESX level or the SAN), then I would recommend going smaller and distribute load accross as many spindles as you can. 

Reply
0 Kudos