On Thu, Oct 15, 2009 at 01:56:40AM +0900, Avi Kivity wrote: > Does virtio say it has a write cache or not (and how does one say it?)? Historically it didn't and the only safe way to use virtio was in cache=writethrough mode. Since qemu git as of 4th Sempember and Linux 2.6.32-rc there is a virtio-blk feature to communicate the existance of a volatile write cache, and the support for a cache flush command. With the combination of these two data=writeback and data=none modes are safe for the first time. -- 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
