Am 24.10.2013 um 20:35 hat Max Reitz geschrieben: > Opening the qcow2 image with BDRV_O_NO_FLUSH prevents any flushes during > the image creation. This means that the image has not yet been flushed > to disk when qemu-img create exits. This flush is delayed until the next > operation on the image involving opening it without BDRV_O_NO_FLUSH and > closing (or directly flushing) it. For large images and/or images with a > small cluster size and preallocated metadata, this flush may take a > significant amount of time and may occur unexpectedly. > > Reopening the image without BDRV_O_NO_FLUSH right before the end of > qcow2_create2() results in hoisting the potentially costly flush into > the image creation, which is expected to take some time (whereas > successive image operations may be not). > > Signed-off-by: Max Reitz <mre...@redhat.com> > Reviewed-by: Eric Blake <ebl...@redhat.com>
Thanks, applied to the block branch. Kevin
