Dear all,
I've been digging into this topic for several days but unfortunately I am still in same point.
Small background:
I have two Proxmox severs, first one, where current Windows 2k8 (VirtualMachine based on KVM) production server is running without any problems and second one, where we would like to migrate Windows VM.
First server has two SATA disks (7200rpm) in hardware RAID1 with core Proxmox installation (1.5)
Second server has two SAS disks (15k rpm) also in hardware RAID1 with Debian Squeeze and Proxmox (1.9) installed manually.
First server:
Second server:
Problem:
After installation, Windows VM on second server is running slower than on first one. What is more, I've noticed, that on second server, just after reboot, when Windows VM is not running, disk performance is normal but it drops when I start VM (I am checking it by dd if=ddfile of=/dev/null bs=8k command , where ddfile has 5.2Mb)
Things, which I already performed:
The funniest thing is, that on first server, this one with slower SATA drives, everything is running fine
Does anybody have any idea what else can be done to improve disk performance on Windows VM?
To be honest currently I am thinking about downgrading KVM from 0.15 to 0.12.5 , but I have no idea if the problem is directly in KVM.
I appreciate any kind of help and support in this topic.
Regards
Piotr
I've been digging into this topic for several days but unfortunately I am still in same point.
Small background:
I have two Proxmox severs, first one, where current Windows 2k8 (VirtualMachine based on KVM) production server is running without any problems and second one, where we would like to migrate Windows VM.
First server has two SATA disks (7200rpm) in hardware RAID1 with core Proxmox installation (1.5)
Second server has two SAS disks (15k rpm) also in hardware RAID1 with Debian Squeeze and Proxmox (1.9) installed manually.
First server:
Code:
proxmox:~# pveversion -v
pve-manager: 1.5-10 (pve-manager/1.5/4822)
running kernel: 2.6.32-2-pve
proxmox-ve-2.6.32: 1.5-7
pve-kernel-2.6.32-1-pve: 2.6.32-4
pve-kernel-2.6.32-2-pve: 2.6.32-7
qemu-server: 1.1-16
pve-firmware: 1.0-5
libpve-storage-perl: 1.0-13
vncterm: 0.9-2
vzctl: 3.0.23-1pve11
vzdump: 1.2-5
vzprocps: 2.0.11-1dso2
vzquota: 3.0.11-1
pve-qemu-kvm: 0.12.4-1
ksm-control-daemon: 1.0-3
proxmox:~# kvm --version
QEMU PC emulator version 0.12.4 (qemu-kvm-devel), Copyright (c) 2003-2008 Fabrice Bellard
proxmox:~# pveperf /var/lib/vz/
CPU BOGOMIPS: 21334.11
REGEX/SECOND: 817464
HD SIZE: 876.38 GB (/dev/sda4)
BUFFERED READS: 58.34 MB/sec
AVERAGE SEEK TIME: 14.67 ms
FSYNCS/SECOND: 782.12
DNS EXT: 188.33 ms
DNS INT: 2.87 ms
Second server:
Code:
root@proxmox2:~# pveversion -v
pve-manager: 1.9-26 (pve-manager/1.9/6567)
running kernel: 2.6.32-6-pve
pve-kernel-2.6.32-6-pve: 2.6.32-55+ovzfix-1
qemu-server: 1.1-32
pve-firmware: not correctly installed
libpve-storage-perl: 1.0-19
vncterm: 0.9-2
vzctl: 3.0.29-3pve1
vzdump: 1.2.6-1
vzprocps: 2.0.11-2
vzquota: 3.0.12-3
root@proxmox2:~# kvm --version
QEMU emulator version 0.15.0 (qemu-kvm-devel), Copyright (c) 2003-2008 Fabrice Bellard
root@proxmox2:~# pveperf /var/lib/vz/
CPU BOGOMIPS: 18619.71
REGEX/SECOND: 813523
HD SIZE: 268.49 GB (/dev/sda7)
BUFFERED READS: 159.58 MB/sec
AVERAGE SEEK TIME: 4.86 ms
FSYNCS/SECOND: 10129.81
DNS EXT: 70.39 ms
DNS INT: 61.44 ms
Problem:
After installation, Windows VM on second server is running slower than on first one. What is more, I've noticed, that on second server, just after reboot, when Windows VM is not running, disk performance is normal but it drops when I start VM (I am checking it by dd if=ddfile of=/dev/null bs=8k command , where ddfile has 5.2Mb)
Things, which I already performed:
- tunning RAID controller (enabling better caching)
- changing Windows disk drivers from IDE to VirtIO
- disabling cache on VM level by adding cache=none to VMID.conf file
The funniest thing is, that on first server, this one with slower SATA drives, everything is running fine
Does anybody have any idea what else can be done to improve disk performance on Windows VM?
To be honest currently I am thinking about downgrading KVM from 0.15 to 0.12.5 , but I have no idea if the problem is directly in KVM.
I appreciate any kind of help and support in this topic.
Regards
Piotr