On Sun, Jan 19, 2020 at 4:42 PM Bohdan Khomutskyi <bkhomuts(a)redhat.com>
wrote:
Hello,
Thanks everyone for posting feedback.
More benchmarking results are available at
https://fedoraproject.org/wiki/Category:Changes/OptimizeSquashFS,
including the 'plain' SquashFS filesystem.
After performing the tests, I personally recommend to use xz compression
with 1MiB block size, without bcj, on a 'plain' squash filesystem -- this
will lead to a reduction of 142MiB on the ISO, compared to the stock Fedora
31 Workstation x86_64 image.
Alternative compression options, such as Zstd, are also mentioned in the
change proposal.
Hmm, and I see I've been completely confused in my last reply, and I
considered the numbers in the first image [1] to be installation times.
Instead they are image creation times. OK. Looking at the new second image
[2], Zstd seems like a clear winner to me at least for QA purposes. With
fine tuning the compression level, we can achieve almost the same file size
for a great installation speedup.
[1]
https://fedoraproject.org/wiki/File:Compression_vs_SquashFS_creation_time...
[2]
https://fedoraproject.org/wiki/File:Compression_vs_installation_time.png