How to disable compression of initrd.img file of Debian Linux 10 buster I want to disable compression of `/boot/initrd.img` file to boot a bit faster. My disk is large enough to accomodate the extra 10MB. To be honest I think that should be the default, who can't afford some megabytes of disk space nowadays. For embedded scenarios, it could be manually enabled. Looking into `/etc/initramfs-tools/initramfs.conf`, there are options to change the compression type COMPRESS: [ gzip | bzip2 | lz4 | lzma | lzop | xz ] but no option to disable compression. I tried `None` and `none`, no effect. As a workabout I manually decompress `initrd.img-4.19.0-8-amd64` using `gunzip`. But each time a kernel update is installed I have to decompress again.

There’s no option provided to do this, but since `mkinitramfs` is a shell script, one can be added without needing to recompile. In `/usr/sbin/mkinitramfs`, look for


case "${compress}" in


Add a “cat” line in the set of options:


cat) compress="cat" ;;


This will allow `COMPRESS=cat` to be specified in `initramfs.conf`.

You will have to re-do this every time `mkinitramfs` is restored from the package (on upgrade).