Launchpad Entry: other-o-arm-preinstall-sd-optimisation
Contributors: Jani Monoses
Packages affected: livecd-rootfs, jasper-initramfs
Significant research has been done on the performance of SD cards. The results indicate that cards perform better with certain classes of filesystem configuration (e.g. alignment matching eraseblocks). The image construction scripts should apply as many of these optimisations as possible when creating preinstalled images to be written to SD. Further, when preinstall images are first expanded, jasper should attempt to optimise the expanded filesystem for the specific media into which it is expanding.
With Ubuntu 11.10 or later, images targeting SD cards are optimised to SD flash geometry, significantly improving performance, reducing application startup time, and booting more quickly.
MMC controllers provide fairly limited bandwidth. Using unoptimised storage configuration can reduce performance by 90% from these already low numbers. These apparently simple fixes will provide a very significant improvement to many common operations.
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BoF agenda and discussion
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