svn commit: r264027 - in head: release share/man/man7

[Nikolai Lifanov]

On 04/02/14 12:06, Glen Barber wrote:
> On Wed, Apr 02, 2014 at 11:55:33AM -0400, Nikolai Lifanov wrote:
>> On 04/02/14 11:51, Glen Barber wrote:
>>> On Wed, Apr 02, 2014 at 10:40:22AM -0500, Brooks Davis wrote:
>>>> On Tue, Apr 01, 2014 at 10:41:27PM +0000, Glen Barber wrote:
>>>>> Author: gjb
>>>>> Date: Tue Apr  1 22:41:26 2014
>>>>> New Revision: 264027
>>>>> URL: http://svnweb.freebsd.org/changeset/base/264027
>>>>>
>>>>> Log:
>>>>>   Add a new release build variable, WITH_COMPRESSED_IMAGES.
>>>>>   
>>>>>   When set to a non-empty value, the installation medium is
>>>>>   compressed with gzip(1) as part of the 'install' target in
>>>>>   the release/ directory.
>>>>>   
>>>>>   With gzip(1) compression, downloadable image are reduced in
>>>>>   size quite significantly.  Build test against head at 263927
>>>>>   shows the following:
>>>>>   
>>>>>    bootonly.iso:		64% smaller
>>>>>    disc1.iso:		44% smaller
>>>>>    memstick.img:		47% smaller
>>>>>    mini-memstick.img:	65% smaller
>>>>>    dvd1.iso:		untested
>>>>>   
>>>>>   This option is off by default, I would eventually like to
>>>>>   turn it on by default, and remove the '-k' flag to gzip(1)
>>>>>   so only compressed images are published on FTP.
>>>>
>>>> I'd recommend testing xz compression as well.  With UFS images of a full
>>>> world the savings vs gzip are significant (more than 30% IIRC, but it's
>>>> need more than a year since I checked so I'm a bit unsure of the exact
>>>> numbers).
>>>>
>>>
>>> delphij also brought this up.
>>>
>>> I have concerns with xz(1), since there was mention in IRC that Windows
>>> users may have problems decompressing xz-compressed images.  So, gzip(1)
>>> is used because it seems to be the more commonly-supported archive
>>> mechanisms.
>>>
>>> The benefit of xz(1) over gzip(1) was only 50M-ish.
>>>
>>>   -rw-r--r--  1 root  wheel   601M Mar 28 20:18 disc1.iso
>>>   -rw-r--r--  1 root  wheel   381M Mar 28 20:18 disc1.iso.bz2
>>>   -rw-r--r--  1 root  wheel   392M Mar 28 20:18 disc1.iso.gz
>>>   -rw-r--r--  1 root  wheel   348M Mar 28 20:18 disc1.iso.xz
>>>
>>> Glen
>>>
>>
>> How about 7zip (Windows program, not file format)? What would a Windows
>> user use that can decompress gzip and not xz? It was a problem around
>> ~2007, but xz support is no longer rare or exotic.
>>
> 
> I don't know, to be honest.  I have no Windows machines to test, so
> I can only go by what I am told.
> 
> Glen
> 

I just verified it with 7zip for Windows version 9.22. It extracts
.tar.xz archives and decompresses .xz images.

- Nikolai Lifanov