[fedora-virt] tuning fdatasync for kvm?

[Bill McGonigle]

On 04/14/2010 02:04 AM, Dor Laor wrote:
> Do you use cache=off or writethrough?

I'm not consciously setting these and I'm not sure how to determine 
which defaults are being used.  I'm including my qemu commandline if 
that helps - I see on rhbz 505695 that putting "-drive cache=none" might 
help but I'm not sure where I'd configure that.

17164 ?        Sl   464:02 /usr/bin/qemu-kvm -S -M pc-0.11 -cpu qemu32 
-enable-kvm -m 2048 -smp 2,sockets=2,cores=1,threads=1 -name Vista2 
-uuid 03233763-dc83-6cb9-d982-a9a772d99347 -nodefaults -chardev 
socket,id=monitor,path=/var/lib/libvirt/qemu/Vista2.monitor,server,nowait -mon 
chardev=monitor,mode=readline -rtc base=localtime -boot c -drive 
file=/var/lib/libvirt/images/Vista2.img,if=none,id=drive-ide0-0-0,boot=on,format=raw 
-device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 
-drive file=/dev/sr0,if=none,media=cdrom,id=drive-ide0-1-0 -device 
ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 -device 
rtl8139,vlan=0,id=net0,mac=52:54:00:02:54:b5,bus=pci.0,addr=0x4 -net 
tap,fd=24,vlan=0,name=hostnet0 -chardev pty,id=serial0 -device 
isa-serial,chardev=serial0 -usb -device usb-tablet,id=input0 -vnc 
127.0.0.1:1 -k en-us -vga cirrus -device 
AC97,id=sound0,bus=pci.0,addr=0x6 -device 
virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3

Thanks,
-Bill

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