CSV IO high latency/queues when running backups

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Re: CSV IO high latency/queues when running backups

Veeam Logoby pterpumpkin » Mon Feb 06, 2017 11:11 pm

jaredplaisted wrote:Just a quick question how many VM's per CSV do you have?

Sharing something we encountered about 2 years ago when we first started using Hyper-V 2012 R2 which maybe relevant.

We used to have similar issues to what you describe, back then we had large CSV's (3PAR) with approximately 20-30 vms per CSV and experienced latency and VM freezing temporarily when ever backups ran, even if backing up a single VM every other VM in the same CSV would get hit bythe issue, regardless of throttling limits, software or hardware vss provider the issue persisted. This freezing/latency would only occur during the first part of the Backup job while the snapshot is being created, after the snapshot was created and the backup began reading/transferring data performance would return to normal.

Since we re-architected our CSV's and reduced the number of VM's per CSV down to 5-10 we no longer encounter the issue, we can run mutliple concurrent backups across multiple CSV's and don't experience any latency or issues now.

We do indeed have a large number of VM's per CSV (20-30). Reducing the number of VM's and increasing the number of CSV's could be a good idea.
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Re: CSV IO high latency/queues when running backups

Veeam Logoby Andreas Neufert » Thu May 24, 2018 8:07 am

Another customer had an issue with ODX and the Storage.

Deaktivation of the SSD trim helped in that case. Please check with Microsoft Support if this is the case.

The solution was the following reg key:
Set-ItemProperty hklm:\system\currentcontrolset\control\filesystem -Name "DisableDeleteNotification" -Value 1
Andreas Neufert
Veeam Software
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