On Thu, 01/23 15:42, Kevin Wolf wrote: > Am 23.01.2014 um 08:10 hat Fam Zheng geschrieben: > > Previously the field is wrong: > > > > $ ./qemu-img create -f vmdk -o subformat=streamOptimized /tmp/a.vmdk 1G > > > > $ ./qemu-img info /tmp/a.vmdk > > image: /tmp/a.vmdk > > file format: vmdk > > virtual size: 1.0G (1073741824 bytes) > > disk size: 12K > > Format specific information: > > cid: 1390460459 > > parent cid: 4294967295 > > >>> create type: monolithicSparse > > <snip> > > > > Signed-off-by: Fam Zheng <f...@redhat.com> > > Thanks, applied to the block branch. > > By the way, I tried converting a raw image to streamOptimised and got > this: > > qemu-img: Could not write to allocated cluster for streamOptimized > qemu-img: error while writing sector 63: Input/output error > > The problem seems to be that qemu-img tries to be clever and doesn't > write out sparse parts, which breaks up the first cluster into multiple > write requests. Adding -S 64 makes it work. Should we change something > to get a working default? >
I think we should make qemu-img even cleverer to not do this with compressed image like this. It was once in my todo list but I forgot to complete it. I'll pick it up. Thanks, Fam
