CFQ or deadline

[sahostking]

Hi

We noticed that default install of proxmox 3.4 and and proxmox 4 is set to deadline?

We use HW Raid 10.

What is recommended?

I thought CFQ would be recommended as some features are missing like ionice etc. on deadline?

 

[tom]

depends on your use case, hardware and workload.

test different settings, see also:
http://pve.proxmox.com/wiki/IO_Scheduler

 

[sahostking]

Thanks. If we host around 10 VPS servers and for one VPS to not cause trouble for the rest and we use hardware raid 10 with SATA Enterprise disks.

Should we use CFQ. I changed it now to CFQ from deadline and don't see much difference yet.

 

[gkovacs]

In our experience CFQ performed much worse under high IO load than deadline (on Adaptec HW RAID10). Especially during LVM snapshot backups the whole server slowed to a halt.

Deadline or NOOP are the two best candidates if you are using a RAID controller that has it's own IO queue, so requests are reordered again at the hardware level as the OS knows nothing about the disk layout.

 

[sahostking]

tried it and looks like you may be right. sticking to deadline