08-18-2021 08:19 AM
Good afternoon all my second question for today.
I was wondering what speed is considered fast for a VM backup. I was bench testing backups to VVOL and sending the backups to a dev/nul device I got an average of around 100,000-120,000 KB/sec reported by the NetBackup java GUI. Doing a single VM yielded around 190,000KB/sec for that client.
08-18-2021 02:07 PM
08-19-2021 07:02 AM
A good speed will all depend on what the bottleneck in your environment is. If you know the data flow of your environment then you can figure that out. It sounds like you have done some benchmarking so know what it theoretically could do on a good day.
But going on the question of speeds in the GUI, then all i can say is it can be misleading, especially if deduplication and/or CBT is involved. As VMs always reports the size of the backup as the size of the whole VM regardless of if it was a differential or full, then the speed listed is if it thinks it has transferred all that data, even if it only transferred a fraction due to deduplication and/or CBT. Only the initial full backup do you get a real feel of what speeds you are achieving on the underlying network.
Just as an example, a 14.5TB VM in one of my environments thinks it is going at 2,784,084 KB/Sec on an 8Gb SAN due to dedupe/CBT.
08-19-2021 08:09 AM
Hello @Nick_Morris ,
I am interested in what you mentioned,
so the reported throughput on Vmware backup job isn't really the speed of the backup? do you know how to measure the real speed?
08-19-2021 09:19 AM
If you have accelerator enabled, I'd take more notice in the bytes sent part (as only that bit has been sent over the network) and then convert it to kilobytes and then divide by seconds it took for the backup as something more real of throughput.