HPE EVA Storage

Slow expansion of vdisk on MSA2312fc

 

Slow expansion of vdisk on MSA2312fc

Hi.

We have a MSA2312fc with dual controllers that before the expansion hade 3 1TB SATA drivers. Late last week I added one additional disc and started the expansion of the vdisk. Now, about 5 days later it has just expanded 22%.

Is this normal? I have checked the "system utility priority" and it's set ho high.
Is there any means of speeding the process up?

Best regards,
Johan Christensson
5 REPLIES 5
Niels Vejrup Pedersen
Respected Contributor

Re: Slow expansion of vdisk on MSA2312fc

Hello Johan,

You're correct - the expansion of a vdisk is very slow on the MSA2xxx family..

To my knowledge there is nothing you can do to speed up things.



Regards,
Wickedsunny
Valued Contributor

Re: Slow expansion of vdisk on MSA2312fc

An extract from the MSA reference guide:-

Expanding a vdisk

You can expand the capacity of a vdisk by adding disks to it. Host I/O to the vdisk can continue while the expansion proceeds. You can then create or expand a volume to use the new free space. You can expand only one vdisk at a time. The RAID level determines whether the vdisk can be expanded and the maximum
number of disks the vdisk can have.


NOTE: Expansion can take hours or days to complete, depending on the vdisk's RAID level and size, disk speed, utility priority, and other processes running on the storage system. You can stop expansion only by
deleting the vdisk.
Patrick Terlisten
Honored Contributor

Re: Slow expansion of vdisk on MSA2312fc

Hello,

expansion can take a lot of time on a MSA2xxx. If you're using RAID 5 on the vdisk you expand, the MSA will initialize all blocks (parity calculation etc.). And with 1 TB drives this could take a lot of time. Expansion is a low priority process.

Is there a lot of IO? How much free space was there before you start the expansion?

Best regards,
Patrick
Best regards,
Patrick
BennyO
Advisor

Re: Slow expansion of vdisk on MSA2312fc

Here's a question for you. Can or should you expand a volume size while the vDisk is expanding? I have about 1TB of free space on a vDisk I want to expand a current volume, however the vDisk is in the process of expanding onto another drive I added to the array.
Thanks
BT
Eemans Dany
Honored Contributor

Re: Slow expansion of vdisk on MSA2312fc

hi,

when you are expanding or rebuilding on an MSA it will perform his task one by one.

The MSA cannot perform 2 expantions at the same time or a rebuild and an expansion at the same time.

The first job must be completed before the next will start.

Dany