Hello David,

As an author of this change, I'd like to comment on the options provided:

1) Reduce the ISO image size.
2) Improve installation time.
3) Improve image composition time.

All three can be achieved at the same time. 

1) Using the best compression with plain SquashFS will reduce the ISO image size.

2) Let's consider numbers in real terms: without multi-core decompression, higher compression in my tests does increase installation time by 30 seconds -- that's insignificant.
With the introduction of multi-core decompression, as I suggest in https://github.com/rhinstaller/anaconda/pull/2292, this increase will be compensated and real installation time will be even lower.

3) By disabling the BCJ filter, image composition time will be reduced by 50%, in real teams on a 4-core x86-64 system, that translates to 5 minutes. This number should be multiplied by the number of Fedora spins times hardware architectures, to get real savings in compose time.
There could be other than compression algorithm optimizations, that can be implemented to reduce compose build time. 

I'd suggest not selecting any specific area to concentrate on, but to achieve an all-good solution that will combine the benefits, without specializing in one particular area.

On Thu, Feb 6, 2020 at 10:02 PM Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> wrote:
On Thu, Feb 06, 2020 at 03:34:23PM -0500, David Cantrell wrote:
> On Mon, Feb 03, 2020 at 05:22:55PM +0100, Nicolas Mailhot wrote:
> >Hardware with low connectivity or low storage (chromebooks, vms)

> Your note about Chromebooks here is good.  I don't have a Chromebook
> and do not know the main issues faced on those systems.

Re-reading, I don't grok this. The compression of the installation
disk or live image is irrelevant to how big the disk of the *target*
machine is. I don't think you'd ever store the live image on a VM,
and even on the chromebook, if it is used for download and needs to
store a temporary copy, a few percent difference wouldn't really matter.
(A permanent difference in installed size would be more meaningful,
but that's not what we're talking about here.)

devel mailing list -- devel@lists.fedoraproject.org
To unsubscribe send an email to devel-leave@lists.fedoraproject.org
Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org

Bohdan Khomutskyi, RHCE
Release configuration management engineer, PnT DevOps
Red Hat Czech s.r.o
T: +420532270289     IRC: bkhomuts