I have a question about right cache policy for KVM using LVM and hardware raid-controller.
So from the bottom: 1. We have LSI RAID controller 9260, 512Mb cache and BBU. Later we also will have CacheCade(SSD Drive as a cache) license and will use SSD. Now controller have virtual drives configured with "write back" and "Disak cache policy:disabled"
Virtual drive presented to LVM. LVM as i know doesn't have any cache policy.
On KVM level - disk attacehd to guest system as virtio-scsi and cache policy set to writethrough.
So question is how to get maximum drive speed in guest and not afraid of power shutdown.
I suppose if i will set virtio-scsi drive policy to "write-back" KVM will use host memory for caching guest io.
So i want to ask if we have optimum configuration now?
Guest system is Windows Server 2012R2 and NTFS. Host system is Centos 6.7 updated.