On Thu, Mar 05, 2015 at 11:48:08AM -0700, Mike Ruckman wrote: > Fellow cloudies, > > The recent builds of our images are v3 qcow2 (also known as qcow3). > This presents a problem for our testing, since the openstack instances > we have access to don't support v3, only v2. The only difference > between v2 and v3 are some performance enhancements - Right, just some details on the said performance enhancements in QCOW2 v3 format, from my notes (about a year old) from an earlier discussion w/ some QEMU developers, the two new features in v3 of QCOW2: (1) lazy_refcounts -- A performance optimization interesting only when using 'cache=writethrough'. Useful when guest crashes or powers off. (2) Zero clusters -- Useful for (disk) image streaming over slow networks. > so the question is, should we produce v2 images instead of v3 for > easier testing? > This would require us to request a tweak from releng to get the > correct format, but would stop us from having to use a workaround [0] > to test (and I worry about testing a converted image - because then we > rely on "well, it *should* be the same" for our test results). > > Thoughts? > > [0] qemu-img amend -f qcow2 -o compat=0.10 <image.qcow2> -- /kashyap _______________________________________________ cloud mailing list cloud@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/cloud Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
