On Fri, 2012-03-16 at 20:28 -0700, John Reiser wrote: > Compressing the initramfs uses gzip only and not pigz where available. > This costs 11 seconds; see dracut. > There is a new, 100-second long, I/O bound section of pungi(lorax) just > after compressing the initramfs. Much of the speedup of treebuilder > has been lost to this delay. Look, image build speed has never been a priority in any of this work. If treebuilder sped things up that's cool, but that was just a happy accident. The goal of the 'noloader' branch was to reduce runtime memory usage[1] and make anaconda's initramfs easier to maintain[2] and debug[3]. The goals for 'treebuilder' were similar: reduce runtime memory usage and make the image build tools more flexible and easier to maintain and debug. In both cases we've made deliberate choices that resulted in reduced memory usage or image size at the expense of build time. For example, using "-Xbcj=$arch" with mksquashfs roughly doubles compression time but reduces the runtime image size by ~2M (about 2%)[4]. This is totally acceptable to me. An extra 90 seconds during the build saves time and RAM for *every person who downloads images*. I'm sure we'll get around to optimizing for build time eventually (and/or adding switches for people who want to build *quickly*), but it's just not a priority for us right now. On the other hand, it's obviously a priority for *you* - why is that? What are you trying to accomplish where an extra 100 *seconds* to build an image is a problem? I'd really like to know what you're trying to do. Maybe we can help you find a better solution, or at least understand your use-case better and maybe add features/options to help. -w [1] Early tests indicate we should be using ~256MB less RAM, which means we can move the minimum to 512MB for graphical installs. More work could be done here. [2] Maintenance is going to be unquestionably easier - we removed ~14,000 lines of code! [3] Just having a shell in initramfs makes things unbelievably easier than they were with 'loader'. [4] You can disable bcj by putting the following in /etc/lorax/lorax.conf: [compression] bcj=off _______________________________________________ Anaconda-devel-list mailing list Anaconda-devel-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/anaconda-devel-list
