Backup jobs progressively slow

[AVLoki]

Hi,

Support case n. 04660273.

Backup jobs, especially ones with large VMs (> 1TB) are getting progressively slower as they run.
They start at more or less 220MB/s processing rate, then progressively get slower until 4-8MB/s.
Backup proxy is a VM wih 4vCPU, 12GB ram. repository is a SMB share on a QNAP nas with 8xHDD 7200rpm RAID6.

Bottleneck is sometimes stated as the proxy, sometimes as the target.

May be unrelated, but having this issue since upgrading to v10a from v9.5u4.

Anything that i can check on the proxy itself?
Made some brief tests and NAS does't look like it's overloaded, since i can copy a large file on the same share at full speed...

[Dima P.]

Hello AVLoki,

Can you clarify what is set as a gateway for your SMB repository? Thanks!

[PaulNSW]

I had a similar issue with my QNAP TS-869U-RP

You can ask support to refer to case 03447325 (and 01185421, 03114029, 03120595, 03122559)

I think I got a hotfix and was also told to edit a registry setting
path=HKEY_LOCAL_MACHINE\SOFTWARE\Veeam\Veeam Backup and Replication\
name=UseUnbufferedAccess
type=D_WORD
value=1

However, this had some adverse effects on my replications, giving a "file in use" error until I received a hotfix

With UseUnbufferedAccess set at 0, backupcopy performance to the QNAP still gradually slows down.

With UseUnbufferedAccess set at 1, backupcopy performance remains constant.

[AVLoki]

Can you clarify what is set as a gateway for your SMB repository? Thanks!

Gateway is the Veeam server itself.

Little update: i switched to NFS repository and now it's much faster, even faster than before.
Now the only thing that i've been banging my head to is the fact that i've a lot of errors and overruns on nas side, this both with SMB and NFS, and only on 10GB nics. If i switch to 1GB nics, everything runs smoothly (even if it's slower).

PaulNSW, the nas we're using is a QNAP TS-832XU-RP, so not sure if it's a QNAP new firmware issue or anything else.
What kind of hotfix did they provide? Firmware patch?

[Dima P.]

Thanks for sharing the updates! I do remember some issues with QNAP firmware related to SMB access (something was throttling the writes), but unfortunately cant find any related post. Is it possible to check if the latest firmware works better?