Arch Linux

zetac

Member

Registered: 2024-10-25

Posts: 1

Compression of Initramfs.img on a compressed BTRFS /boot partition

Hello.

This is kind of a general question.

My /boot directory is a separate disk partition fomatted/mounted as compressed BTRFS.

If BTRFS is handling compression, can I just turn off compression of the initramfs file in /etc/mkinitcpio.conf?

BTRFS gives weird stats for the /boot FS without compression, am not sure what to trust.

Thanks in advance.

Sam

mithrial

Member

Registered: 2017-03-05

Posts: 51

Re: Compression of Initramfs.img on a compressed BTRFS /boot partition

Which weird stats?

frostschutz

Member

Registered: 2013-11-15

Posts: 1,472

Re: Compression of Initramfs.img on a compressed BTRFS /boot partition

Grub supports btrfs data compression (zstd and lzo only?). However this means that Grub has to do the uncompressing and then pass the uncompressed image to the kernel.

This could be slower than the oldschool way of uncompressed filesystem, compressed initramfs, and leaving the decompression to the kernel. It could also be worse in terms of error handling.

However only one way to find out. Just do it and compare and see how it turns out.