On Mon, Jul 15, 2013 at 01:06:26PM +0200, Lukas Zapletal wrote: > On Mon, Jul 15, 2013 at 12:22:22PM +0200, Jaroslav Reznik wrote: > > downloadable cloud images (in qcow2 and raw.xz format) produced and released > I know that it is convenient to expose qcow2 images uncompressed so > users are able to upload them directly into clouds via httpd. Qcow2 is > compressed already by default (is that zlib?) so I am wondering if there Just for clarity, qcow2 can be compressed or uncompressed; these are compressed. > is any way of re-compressing the image with "-9" option so we are sure > the size is the best we can offer. I think this may just come down to deflate (zlib) vs lzma (xz). A comment in the qemu-img source code says "best compression, small window, no zlib header" -- I'm kind of guessing, but I expect that the small window size was chosen on purpose for when the image is actually used. > Currently qemu-img does not offer that. Size comparison between qcow2 vs > raw.xz shows that there are most likely some gaps we can fill in the > qcow2 size. > Just throwing in some ideas. Maybe not that relevant for this, I > apologize. Probably not relevant, but I'm open for any approaches for improvement. -- Matthew Miller ☁☁☁ Fedora Cloud Architect ☁☁☁ <mattdm@xxxxxxxxxxxxxxxxx> -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel
