RAID block size

[BitRausch]

Hi @all,

I am setting up a new PVE Server with a hardware raid 10 configuration.
I was wondering what the best block size would be. I am planing to run KVM Windows Server 2008 and SBS 2008 Server with 100 to 200 GB qcow2 files.
Should I go for a block size like 256 kb because of the big qcow2 files or should I set it to more like 64 kb since this are windows server and with that comes more smaller files...

Is there a recomandation or suggestions ?

kind regards
BitRausch

 

[BitRausch]

correction: I meant strip size

What is the best strip size for raid 10 and pve?
What strip size do you guys use on your raid?

kind regards
BitRausch

 

[udo]

Hi,
i used a stripe size of 64k. So i can use the power of two drives when i read files bigger than 64k.

CLI> vsf info vol=1
Volume Set Information
===========================================
Volume Set Name : ARC-1210-VOL#00
Raid Set Name   : Raid Set # 00
Volume Capacity : 600.0GB
SCSI Ch/Id/Lun  : 00/00/00
Raid Level      : Raid1+0
Stripe Size     : 64K
Member Disks    : 4
Cache Mode      : Write Back
Tagged Queuing  : Enabled
Volume State    : Normal
===========================================

But i haven't compare the speed with different strip sizes. I think there are other things that have a bigger impact to the speed (concurrent read/write of differents qcows).

Udo