I have a client with an old installation: PVE4.4 on an OLD HP server, with HW RAID and working BBU.
Waiting to replace it, I'm trying to find ways to speed up VMs.
I saw that most of virtual disks were created with IDE controllers adn writethrough enabled, thus I thought it was an easy win to replace it with a SCSI controller.
It was not.
I tried various settings, the best one with SCSI should be writethrough enabled: but as you can see, Read performance is great but Write is abysmal.
LEFT: IDE
RIGHT: SCSI
Both with writethrough enabled
I tried to use writeback, which sould be ok to use with BBU backed HW RAID, but CyrstalDiskMark crashes consistently with that, thus I dont't trust it.
Any suggestion is welcome.
Waiting to replace it, I'm trying to find ways to speed up VMs.
I saw that most of virtual disks were created with IDE controllers adn writethrough enabled, thus I thought it was an easy win to replace it with a SCSI controller.
It was not.
I tried various settings, the best one with SCSI should be writethrough enabled: but as you can see, Read performance is great but Write is abysmal.
LEFT: IDE
RIGHT: SCSI
Both with writethrough enabled
I tried to use writeback, which sould be ok to use with BBU backed HW RAID, but CyrstalDiskMark crashes consistently with that, thus I dont't trust it.
Any suggestion is welcome.