Veeam Agent for Windows with Throttling runs very slow

[arseny_v]

We're evaluating VEEAM Agent for Windows 2.2.0.589 as a solution to back up our barebone MS SQL Server 2017 on Windows Server 2016, backing up whole server using installed VEEAM CBT driver.

The disk is 4Tb Intel P4600 NVMe SSD, pretty fast one, with ~2Tb used in databases and system files.
Since we're running 24/7 workload, we're performing tests of backup task impact on our regular database activities, since the impact is our main concern.

A few tests, performed at similar server load showed that:

- with the 'Throttling' option disabled, usual once-a-day Diff backup takes around 20-30 minutes to complete (~5 minutes for creating VSS snapshot, ) at processing rate around 500-700 MB/s.

- with 'Throttling' option enabled, the processing rate drops to 700KB/s, roughly a thousand times slower. So, the same once-a-day Diff backup takes considerably longer than 24 hours.

We know that 'Throttling' checked means that the backup process is given a lower priority on client side, but what we're confused about is is such a performance drop an expected behavior?

There are around 80 databases of various size and average load on our database server, no hardcore highload peaks though - just regular activity.

Any help or suggestion is welcome, thank you.

[arseny_v]

Found a thread where quite slow Windows Agent performance with Throttling enabled was mentioned: veeam-agent-for-windows-f33/backup-perf ... 28529.html

[Dima P.]

Hello and welcome the the community Arseny.

It looks expected since the backup process takes lowest priority (which means all the resources are given to the process started by SQL server). If you are backing up you machine during non production hours - try to keep throttling option disabled and let us know how it goes. Cheers!

[arseny_v]

Dima, thank you for clarification, regards =)