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Showing posts from November, 2023

Ubuntu 23.10 significantly reduces the installed kernel footprint

Photo by Pixabay Ubuntu systems typically have up to 3 kernels installed, before they are auto-removed by apt on classic installs. Historically the installation was optimized for metered download size only. However, kernel size growth and usage no longer warrant such optimizations. During the 23.10 Mantic Minatour cycle, I led a coordinated effort across multiple teams to implement lots of optimizations that together achieved unprecedented install footprint improvements. Given a typical install of 3 generic kernel ABIs in the default configuration on a regular-sized VM (2 CPU cores 8GB of RAM) the following metrics are achieved in Ubuntu 23.10 versus Ubuntu 22.04 LTS: 2x less disk space used (1,417MB vs 2,940MB, including initrd) 3x less peak RAM usage for the initrd boot (68MB vs 204MB) 0.5x increase in download size (949MB vs 600MB) 2.5x faster initrd generation (4.5s vs 11.3s) approximately the same total time (103s vs 98s, hardware dependent) For minimal cloud images that do not in