Slow windows guest disk

[quickcrx702]

I'm getting relatively slow disk performance on the host, which I guess I could live with, but I'm getting really slow disk performance on a Windows 2003 VM that I p2v'd. I've tried both IDE and virtio for storage, and each is giving less than 5MB/sec as measured by iometer.

Here is the output of pveperf on the host.

root@host:~# pveperf
CPU BOGOMIPS:      21279.91
REGEX/SECOND:      1005926
HD SIZE:           9.84 GB (/dev/mapper/pve-root)
BUFFERED READS:    81.01 MB/sec
AVERAGE SEEK TIME: 4.44 ms
FSYNCS/SECOND:     2639.31

Here is info from the Dell Openmanage utility I installed on the host. I wanted to keep things vanilla and not install anything on the host, but Openmanage+DRAC can be a real life saver on Dell servers.

root@host:~# omreport storage vdisk controller=0
List of Virtual Disks on Controller PERC 5/i Integrated (Embedded)

Controller PERC 5/i Integrated (Embedded)
ID                        : 0
Status                    : Ok
Name                      : Virtual Disk 0
State                     : Ready
Hot Spare Policy violated : Not Assigned
Encrypted                 : Not Applicable
Layout                    : RAID-10
Size                      : 272.25 GB (292326211584 bytes)
Device Name               : /dev/sda
Bus Protocol              : SAS
Media                     : HDD
Read Policy               : Adaptive Read Ahead
Write Policy              : Write Back
Cache Policy              : Not Applicable
Stripe Element Size       : 128 KB
Disk Cache Policy         : Disabled

pve-manager/2.1/f9b0f63a is the output of pveversion

I have four 15k SAS drives in raid 10. I don't remember the exact number, but I'm pretty sure that I was getting over 100MB/s on Windows bare metal measured by iometer. It has 256mb battery backed cache, and if memory serves me right the raid options all look good.

Is there anything that you guys think I'm missing, or have any advice? Thanks in advance.

 

[spirit]

what storage type do you use ? (.raw, .qcow2,lvm ?). which cache mode ? (none,directsync,writethrough,writeback) ?


can you post you vm config file ?

 

[quickcrx702]

Raw storage and no cache.

root@host:~# cat /etc/pve/qemu-server/100.conf
bootdisk: ide0
cores: 2
ide2: local:iso/virtio-win-0.1-30.iso,media=cdrom
memory: 8192
name: xxxxx
net0: virtio=xx:xx:xx:xx:xx:xx,bridge=vmbr0
onboot: 1
ostype: wxp
sockets: 2
virtio0: local:100/vm-100-disk-1.raw


Thanks

 

[spirit]

your config seem clean,
can you try with writethrough ?
Did you have tried with linux guest to compare performance ?