On Mon, Oct 22, 2012 at 07:36:34AM -0600, Ben Clay wrote: > Forwarding this to the KVM general list. I doubt you folks can help me with > libvirt, but I was wondering if there?s some way to verify if the cache=none > parameter is being respected for my KVM guest?s disk image, or if there are > any other configuration/debug steps appropriate for KVM + virtio + cgroup. Here's how you can double-check the O_DIRECT flag: Find the QEMU process PID on the host: ps aux | grep qemu Then find the file descriptor of the image file which the QEMU process has open: ls -l /proc/$PID/fd Finally look at the file descriptor flags to confirm it is O_DIRECT: grep ^flags: /proc/$PID/fdinfo/$FD Note the flags field is in octal and you're looking for: #define O_DIRECT 00040000 /* direct disk access hint */ Stefan -- 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
