Changing dpkg-deb default compression from gzip to lzma for Hardy

Thilo Six T.Six at
Tue Dec 18 10:09:50 UTC 2007

Emmet Hikory wrote the following on 18.12.2007 01:51
> On Dec 18, 2007 9:09 AM, Thilo Six wrote:
>> comparation of a whole install (download time + extract time):
>> download time gz (39084/384)= 101.78s +  14.278s = 116.06s
>> download time 7z (27358/384)=  71.24s + 143.783s = 215.02s
>     Comparisons like this have far too many factors (as you mentioned
> separately).  I've seen Ubuntu used on a 3GHz Core2 Duo over ISDN and
> on a 400MHz Pentium IIIs with ethernet connectivity to the mirrors,
> which lead to compltely different results to the tests above.

That´s why is said:
depending on who you ask i think the answer will be quite different.
Someone on a modem line will much appreciate the 30% less time downloading
(7z), someone with a fat DSL cable and weak cpu will tend to prefer gz.

actually i realised the numbers above are wrong because i mixed up byte with bit.
So actually :
download time gz (39084*8/384)= 814.25s +  14.278s = 828.52s
download time 7z (27358*8/384)= 569.95s + 143.783s = 713.74s

would be right.

As you can see 7z is better in comparation of the whole install prozess.

Also interressting:
	extract time / download time
gz:	14.278s	     /  814.25s	= 1.8%
7z:	143.783s     /  569.95s = 25.3%

This means (at least here) i spend 99% of the install time downloading OOo
with gz and only 75% with 7z.

Personally i tend to prefer LZMA (aka 7z) also for package compression and
maybe *if we don´t want to that as default* for all packages, then lets use
it at least for the big ones - lets say .deb that are bigger then 20MB, or so.

Only with OOo core moved from gz to 7z we save: 39084 - 27358 = 11726kB on
the CDs!!

I can remember disscuions on ubuntu-devel to save that amount of space were
it wasn´t that easy.



key: 0x4A411E09

More information about the Ubuntu-devel-discuss mailing list