> Haven't followed the thread in great detail, but has anyone tried > putting the virtio disk back into rotational mode? Hello. I haven't had a chance to try all the suggestions in the thread so far. However, I did just run some tests with block queue rotation settings tonight. For the problem where mkfs.ext3 on a virtio disk image (raw image, not pre-allocated) the timing went from like 27 minutes for a 10gb fs down to just over 2 minutes. So that was a huge difference. For the linux kernel build test, there was a difference, but less dramatic. I'd say the performance is still below what I expected. I haven't given up yet, there is more to try in the thread. I just wanted to post these results. The HW in use is the same as in the rest of the tread, including the virtio disk type. Since my last post, fedora 11 updates have been applied to the system. Timing with the rotational stuff set to 1... real 14m13.015s user 29m42.162s sys 8m37.416s To confirm this was really better, I halted the virtual machine and restarted it without doing setting the rotational values to 1. I got this timing: real 16m50.829s user 29m33.933s sys 9m4.905s And finally, to confirm the numbers on the host with no guest running... The same disk/filesystem, now mounted on the host instead of the guest, gave this timing: real 6m13.398s user 26m56.061s sys 5m34.477s For the guest runs, qemu command was as follows. For later tests, I will combine the queue rotation setting with the other suggestions. /usr/bin/qemu-kvm -M pc -m 4096 -smp 8 -name f11-test -uuid b7b4b7e4-9c07-22aa-0c95-d5c8a24176c5 -monitor pty -pidfile /var/run/libvirt/qemu//f11-test.pid -drive file=/var/lib/libvirt/images/f11-test.img,if=virtio,index=0,boot=on -drive file=/dev/sdb,if=virtio,index=1 -drive file=/var/lib/libvirt/images/test.img,if=virtio,index=2 -net nic,macaddr=54:52:00:46:48:0e,model=virtio -net user -serial pty -parallel none -usb -usbdevice tablet -vnc cct201:1 -soundhw es1370 -redir tcp:5555::22 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
