We've been doing some testing with KRBD and Writeback, and have noticed -massive- performance gains with the two paired in Windows Server 2019 and OpenBSD guests.
Proxmox 6.3
22 2tb SSD OSD's
Ceph 14.2.22
I've attached crystaldiskmark screenshots of the latency in the VM.
KRBD No Writeback:
KRBD Writeback:
libRBD No Writeback:
libRBD Writeback:
These were all tested on the same pool, VM shut down and restarted between each test.
The read and write #'s show the same huge contrast.
KRBD Writeback:
libRBD Writeback:
The magic is definitely somewhere in the krbd and writeback combo.
Just wondering if anyone else has seen this crazy difference, as well as wanted to let people know that playing with these things can make a huge difference.
Proxmox 6.3
22 2tb SSD OSD's
Ceph 14.2.22
I've attached crystaldiskmark screenshots of the latency in the VM.
KRBD No Writeback:
KRBD Writeback:
libRBD No Writeback:
libRBD Writeback:
These were all tested on the same pool, VM shut down and restarted between each test.
The read and write #'s show the same huge contrast.
KRBD Writeback:
libRBD Writeback:
The magic is definitely somewhere in the krbd and writeback combo.
Just wondering if anyone else has seen this crazy difference, as well as wanted to let people know that playing with these things can make a huge difference.