On Sun, 04 Feb 2024 09:15:42 +0100 Tollef Fog Heen
wrote:
> Package: initramfs-tools-core
> Version: 0.142
> Severity: wishlist
>
> It would be nice if initramfs-tools-core used zstdmt (multi-threaded)
> instead of plain zstd when creating the initramfs. On my system, that
> saves about 15% of the time spent building the initramfs.
>
> The following change seems sufficient:
>
> --- /usr/sbin/mkinitramfs~2022-07-12 23:51:34.0 +0200
> +++ /usr/sbin/mkinitramfs 2024-02-04 09:09:07.614462279 +0100
> @@ -227,7 +227,7 @@
> fi
> ;;
> lz4) compress="lz4 ${compresslevel} -l" ;;
> -zstd)compress="zstd -q ${compresslevel}"
> +zstd)compress="zstdmt -q ${compresslevel}"
> # If we're not doing a reproducible build, enable multithreading
> test -z "${SOURCE_DATE_EPOCH}" && compress="$compress -T0"
> ;;
The man page of zstdmt says that is equivalent to "zstd -T0". As you can
see from the code, -T0 is added in case not doing a reproducible build.
So this change should have no performance impact. A test on a Raspberry
Pi Zero 2 did not reveal any performance difference.
--
Benjamin Drung
Debian & Ubuntu Developer
