Impact of Thin Provision disks - speed / performance

[egroeg]

Hi form.

Is anyone able to provide a quick answer to what the imapact is of running VM with thin disks versus thick when running Veeam to back them up?

I've read this doc which suggests it should make a difference, but have also read varying other material.

I'm running Veeam v8, with vSphere 5.5 + VM version level 8.

http://www.veeam.com/files/whitepapers/ ... covery.pdf

Thanks

[PTide]

Hi,

With thin provision there is no extra time expenditures for zero-blocks search, as there are none in a thin disk. With thick provisioning extra time spent for search-and-exclude empty spaces from a backup file. Also, if you use lazy zero thick, there is a chance that some old data will be backed up as well during initial full backup because it has not been zeroed out while allocating .vmdk.

Thank you.

[PTide]

UPDATE:

That applies to newly created disks only. Thin disks are not reduced when data is being deleted from guest OS thus some "unused" space still might be scanned. Also please see this post and this thread

Thank you.

[peeky1323]

Hi,

We host some Veeam Cloud Backups for a few customers. The repository is on a Hyper-V VM. I was wondering if anyone knows what the performance gain was for having the repository VM disk Fixed instead of Dynamic if any. Given that the bottleneck is the WAN connection, is there a noticeable gain for using Fixed over Dynamic?

Kind regards,

Matt

[PTide]

Hi,

Fixed vs Dynamic disk in a Hyper-V is basically the same as Thick vs Thin in a vSphere. Please see the thread for details.

Thank you.

[peeky1323]

Hi,

I understand that, and I understand performance in a production environment where the disks are hosting services, files etc. But as this is a Cloud repository, I was wondering if the Bottleneck of the WAN would outweigh any performance increase. I could not find any information on that.

Thanks,

Matt

[veremin]

Just ask your tenants regarding the major bottleneck they see in job statistics. Most likely, it's connectivity between their site and yours (WAN). So, modification of target repository wouldn't result in noticeable performance increase. Thanks.