On 07/09/2009 09:01 PM, Erik Jacobson wrote:
Please drop -usbdevice tablet and set the host I/O scheduler to
deadline. Add cache=none to the -drive options.
yes, these changes make a difference.
Before starting qemu-kvm, I did this to change the IO scheduler:
BEFORE:
# for f in /sys/block/sd*/queue/scheduler; do cat $f; done
noop anticipatory deadline [cfq]
noop anticipatory deadline [cfq]
SET:
# for f in /sys/block/sd*/queue/scheduler; do echo "deadline"> $f; done
CONFIRM:
# for f in /sys/block/sd*/queue/scheduler; do cat $f; done
noop anticipatory [deadline] cfq
noop anticipatory [deadline] cfq
qemu command line. Note that usbtablet is off and cache=none is used in
drive options:
/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,cache=none -drive file=/dev/sdb,if=virtio,index=1,cache=none -drive file=/var/lib/libvirt/images/test.img,if=virtio,index=2,cache=none -net nic,macaddr=54:52:00:46:48:0e,model=virtio -net user -serial pty -parallel none -usb -vnc cct201:1 -soundhw es1370 -redir tcp:5555::22
# rotation enabled this way in the guest, once the guest was started:
for f in /sys/block/vd*/queue/rotational; do echo 1> $f; done
Test runs after make clean...
time (make -j12&& make -j12 modules)
real 10m25.585s
user 26m36.450s
sys 8m14.776s
2nd trial (make clean followed by the same test again.
real 9m21.626s
user 26m42.144s
sys 8m14.532s
That's a scaling of 3.7, still pretty far from the host and even farther
than my results.
Is the numa factor of this machine larger than usual?
--
error compiling committee.c: too many arguments to function
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