Re: [proposal] use xz compression for Debian package by default
On Tue, Aug 28, 2012 at 12:10:18PM +0900, Hideki Yamane wrote:
> We know some packages are better to use gzip, but it's an exception. Using xz
> is best choice for rest 99.99% of packages. We can deal with such exception
> by specifying gzip for that (e.g. openclipart-png).
Or even no compression at all. But this needs to be checked.
> *** what's the best compress option for default? ***
> low CPU : --check=crc32 -> -10% time
You tested this on a CPU without 64-Bit multiplication unit? Otherwise
it should not be visible.
> low memory : --lzma2=dict=64KiB (or -0) -> use 100KiB mem
I think we could go for -2 or -3. You can't run Debian on anything with
less then 32MiB RAM.
> use arch optimization? : Yes, if we can (*) -> -10% size
No good idea. The doc clearly stats:
| [...] so it generally isn't good to blindly apply a BCJ filter when
| compressing binary packages for distribution.
> *** how to find appropriate compression rate(1, 6 or 9) for xz? ***
> build your package with each option :-)
This is not appropriate. Needing 700MiB to compress is no good idea.
Madness has no purpose. Or reason. But it may have a goal.
-- Spock, "The Alternative Factor", stardate 3088.7