Exchange 2016 backup extremely slow
I'm having a serious performance problem backing up Exchange 2016 running on a Hyper-V VM.
We are using Backup Advanced for Hyper-V (11.7.50064) and all VM's agents are also the same version.
When trying to backup Exchange DB (information store) backup speed oscilates between 460KB/s and 512KB/s as if there was a hard limit though when backing up other VMs on the same host we easily achieve sustained average speeds of 150-200MB/s and higher peaks to the same LTO-7 drive (SAS2 DAS). With a DB size of >90GB this means it would take over 24h to complete a backup. All host's storage is enterprise SSD based (SAS RAID5).
On the Exchange VM I see a constant disc read speed of 1-1.5MB/s when running the backup process.
Any idea or suggestion of where to start looking?
Backing up this complete Exchange VM without using agents (approx. 180GB) finishes in 18min using the same SW/HW.