On Thu, Jun 16, 2011 at 1:44 AM, Anthony Liguori <[email protected]> wrote: >>> That's probably why it's fast, it doesn't preserve data integrity :( >> >> Actually, I misread the code. It does unstable writes but it does do >> fsync() on FLUSH.
On Thu, Jun 16, 2011 at 8:41 AM, Pekka Enberg <[email protected]> wrote: > Yes. That's fine, right? Or did we misread how virtio block devices > are supposed to work? And btw, we use sync_file_range() to make sure the metadata part of a QCOW2 image is never corrupted. The rational here is that if the guest doesn't do VIRTIO_BLK_T_FLUSH, you can corrupt your _guest filesystem_ but the _image_ will still work just fine and you can do fsck on it. Also, Prasad ran xfstests and did over-night stress tests to iron out corruption issues. Now we obviously can't promise that we'll never eat your data but I can assure you that we've done as much as we've been able to with the resources we have at the moment. Pekka -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
