Hi,
i did a simple write test on my system and found out that there is a big
performance difference regarding to write operations between non-xen and xen
kernels.
HW is dual 4-core Xeon5570 with 32GB RAM and FC attached storage with SATA
drives (RAID5).
SW is linux 2.6.32 pv-ops with Xen4.0.0-rc4 on Debian Lenny. There were no
VMs running. I did simple 'dd' write test with 3GB file on LVM partition.
dom0 with 2GB RAM and 2CPU
==========================
linux2.6.32 pv-ops + Xen4.0.0-rc4
title Xen 4.0.0-rc4 / Debian GNU/Linux, kernel 2.6.32
root (hd0,0)
kernel /xen-4.0.0-rc4.gz dom0_mem=2048M dom0_max_vcpus=2
module /vmlinuz-2.6.32 root=/dev/sda6 ro console=tty0
module /initrd.img-2.6.32
#xm vcpu-pin Domain-0 0 0
#xm vcpu-pin Domain-0 1 1
#time dd if=/dev/zero of=zerofile.tst bs=1k count=3145728
3145728+0 records in
3145728+0 records out
3221225472 bytes (3.2 GB) copied, 48.4788 s, 66.4 MB/s
real 0m48.531s
user 0m1.940s
sys 0m12.745s
dom0 with no memory and cpu limit
=================================
linux2.6.32 pv-ops + Xen4.0.0-rc4
title Xen 4.0.0-rc4 / Debian GNU/Linux, kernel 2.6.32
root (hd0,0)
kernel /xen-4.0.0-rc4.gz
module /vmlinuz-2.6.32 root=/dev/sda6 ro console=tty0
module /initrd.img-2.6.32
#time dd if=/dev/zero of=zerofile.tst bs=1k count=3145728
3145728+0 records in
3145728+0 records out
3221225472 bytes (3.2 GB) copied, 15.7325 s, 205 MB/s
real 0m15.735s
user 0m2.312s
sys 0m13.273s
bare metal
==========
linux2.6.32 pv-ops
title Debian GNU/Linux, kernel 2.6.32
root (hd0,0)
kernel /vmlinuz-2.6.32 root=/dev/sda6 ro
initrd /initrd.img-2.6.32
#time dd if=/dev/zero of=zerofile.tst bs=1k count=3145728
3145728+0 records in
3145728+0 records out
3221225472 bytes (3.2 GB) copied, 6.42111 s, 502 MB/s
real 0m6.422s
user 0m0.304s
sys 0m6.024s
Any idea what to check/modify to improve?
thanks,
roman
--
----------------------------------------------------------------------
,''`. [benco] | mailto: benco@xxxxxxx | silc: /msg benco
: :' : -------------------------------------------------------------
`. `' GPG publickey: http://www.acid.sk/pubkey.asc
`- KF = 0DF6 0592 74D2 F17A DACF A5C3 1720 CB7C F54C F429
dmesg
Description: Text document
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|