Will 2 vdisks provide better performance on p2000 G3 FC dual controller SAN with vsphere 5?

[David Borden]

I am torn between creating 1 large volume with a single vdisk for vsphere 5.  I am trying to understand the details regarding the assigning of a vdisk to a specific controller and the performance implications.

If I have only 1 vdisk and 1 large volume in that vdisk will i be limiting myself to half the capable performance with a dual controller array?

Would a better design be to create 2 vdisks with a volume assigned to each vdisk and each vdisk assigned to a different storage controller?

ESXi 5 is set to Round Robin.

Would I see the best performance this way?  The reason I am asking is in the admin guide for P2000 G3 it says that Round Robin Queues I/O to the LUNs on all ports of the owning controller in a round robin fashion providing instant bandwidth improvement. 

So if I only have 1 VDISK then I would effectively be limiting myself to using only that 1 controller for I/O instead of both controllers.  Am I reading this right?

P.S. This thread has been moved from  VMware>General to ESXi. -HP Forum Moderator

[Jan Soska]

Hello,

in my opinion it would be better to create more vdisks. Each disk has its own queue and in some circumstences you can have benefits from more disk queue - especialy in high I/O load.

another saying - some ESX admins prefer creating own vdisk/datastore for each VM :).

We are preparing pretty similar enviroment so I'll do some test what is best for MSA G3.

jan

[Jags_21]

Hi,

I would say having multiple vdisk is better than having single vdisk and all the VM's on it.

Should plan in such way that the VM's which are highly I/O intensive should put on a dedicated datastore (vdisk) and also the vm having huge junk of space allocated a different datastore (vdisk) , all other vm's on a different datastore (vdisk)

Thanks,