On Wed, May 13, 2020 at 5:32 AM Bohdan Khomutskyi <bkhomuts(a)redhat.com> wrote:
It was a long time since the last message in this change proposal.
Recently I was working to reduce the impact of the increased compression ratio on the
installation image size for Fedora. I have achieved outstanding results -- working proof
of concept. With the following change: https://github.com/rhinstaller/anaconda/pull/2292
not only the higher compression does not impact the installation time. In certain cases,
the installation time is even reduced. This is because of the fact the filesystem internal
structure aware process is used to install the system from the SquashFS. The new process
also allows for taking advantage of the multi-core architecture of the system during
installation -- does the decompression on multiple processors in parallel.
The combination of https://github.com/rhinstaller/anaconda/pull/2292
should reduce _both_ the
image size and the installation time. The installation time will be reduced in case the
system is installed from the SquashFS. This is the case in Fedora Workstation.
For optimization of the SquashFS, I will work on requesting the support of the required
functionality in the Pungi compose build software.
Hi, since the feedback was that a higher emphasis be placed on install
time being reduced, even if there was some increase in ISO size (not
without limit, it's a balancing act), I'm still curious how the change
compares when using zstd, all other things being equal.
For example Solus recently changed from xz to zstd in squashfs, and
claim 3-4x faster install times, with some increase in image size.