Shutting down machine while deleting large snapshot

Question

On ESXi 5.1, i started deleting a snapshot some hours ago..

A big snapshot of about 800gb. the machine is an SQL Server.

It is only at 34% on deleting.

can i just shutdown the machine while deleting, in order to do it faster?

Aftermath:

Well just FYI. This is a DB server responsible for our Enterprise Data Warehouse. It runs SQL Server and every day there is a lot of activity because the ETL process is running.

It was a months old snapshot there.

the total time of ETL was 8 hours until yesterday, and after the snapshot delettion it is down to 2,5 hours. Cheers!

Solution

No you can't! The process of deleting the snapshot actually consists of committing the changes that were made in it. ESXi won't let you change power state during this process (forcing it off by taking drastic measures could corrupt your disks)

You can start the process with the VM off but this will only make it quicker if the VM has heavy IO. The downside to this is you can't start the VM part way through either.

If your snapshot is old it will take a long time. Avoid this by using only using snapshots temporarily and removing them as soon as possible.

Comments

[e4rthdog]

the snapshot is from 23/12/2014, but this is our DW server where daily there is a lot of file I/O (staging) and DB I/O (SSI ETL). So i will have to just wait and hope for the best

[duenni]

Are you sure about this? The VMWare Knowledge Base states that an additional snapshot is created when the VM is powered on and one deletes all snapshots. This is to accomodate I/O. So all snapshots are merged to the base disk and the additional snapshot is the last one merged. Should make no difference if the VM is powered off? The I/O snapshot is already created and can also be merged when the VM is off?

[duenni]

See kb.vmware.com/kb/1023657

[HopelessN00b]

@duenni Last time I tried to power off a VM to cancel a consolidation, vCenter returned an error and wouldn't let me change the power state of the VM, so that jives with possible disk corruption. Anyway, I had to wait for the consolidation to complete before I could delete the thing. Sadly, I don't have a nice, snapshot-heavy VM I can sacrifice for testing purposes at the moment.

[JamesRyan]

@duenni there you go, clarified a bit I hope

[duenni]

Thanks, quite interesting. Did not knew that and also never tested it.