It looks like the raw format xz-compressed cloud images that we ship use a very large block size, possibly 192M. This is not ideal and it would be better to use a smaller block size such as 16M so that they can be consumed without having to be uncompressed by nbdkit, or even be used remotely without even downloading them.
(Long story here: https://rwmj.wordpress.com/2018/11/23/nbdkit-xz-curl/ ) I recompressed the Fedora 29 cloud image using a 16M block size and there is about 4% overhead to doing this: before 194278292 after 202874868 At the moment I'm not clear what actual component does the xz compression step, so I don't even know where I could file a bug or who I could discuss this with, nor what the current code looks like. Apparently it's no longer done using appliance-tools. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/ _______________________________________________ devel mailing list -- devel@lists.fedoraproject.org To unsubscribe send an email to devel-le...@lists.fedoraproject.org Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org
