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- Full Name: Rudy
I've scheduled a backup job with direct san access and for some VM's we have a processing rates from 70 MB/s for a 400GB VM to 400MB/s for a 250GB VM.
What might be impacting these processing rates ?
I expect them all to be 400MB/s..
- Product Manager
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- Full Name: Vitaliy Safarov
For full backup, different processing rates are due to a number of empty blocks on the virtual disks (these are skipped, increasing the rate). For incremental runs, the more disk changes have to be processed, the lower processing rate you'll have. And for any run, the processing rate is affected by time required to perform guest processing, guest freeze, snapshot creation/deletion procedures, time required to backup configuration files etc. which may vary between VMs.
It is important to keep in mind that "processing rate" is not throughtput, but total VM size divided by total VM processing time.