xz for the new release tip

xz for the new release tip

[Jan Kratochvil]

Hi,

while currently the sources are release both as .tar.gz and as .tar.bz2 would
not it be worth to start using .xz as a replacement for the .bz2 variant?

13406892 bytes: gdb-6.8.91.20090930.tar.xz  (xz -9)
xz -dc:    real	0m1.226s user	0m1.190s sys	0m0.037s

18453837 bytes: gdb-6.8.91.20090930.tar.bz2
bzip2 -dc: real	0m3.775s user	0m3.755s sys	0m0.019s



Just a tip,
Jan

Re: xz for the new release tip

[Daniel Jacobowitz]

On Wed, Sep 30, 2009 at 10:28:57PM +0200, Jan Kratochvil wrote:
> Hi,
> 
> while currently the sources are release both as .tar.gz and as .tar.bz2 would
> not it be worth to start using .xz as a replacement for the .bz2 variant?
> 
> 13406892 bytes: gdb-6.8.91.20090930.tar.xz  (xz -9)
> xz -dc:    real	0m1.226s user	0m1.190s sys	0m0.037s
> 
> 18453837 bytes: gdb-6.8.91.20090930.tar.bz2
> bzip2 -dc: real	0m3.775s user	0m3.755s sys	0m0.019s

I think that fails any 'widely available' test - I can't even find a
Debian package of it.

-- 
Daniel Jacobowitz
CodeSourcery

Re: xz for the new release tip

[Mark Kettenis]

> Date: Wed, 30 Sep 2009 22:28:57 +0200
> From: Jan Kratochvil <jan.kratochvil@redhat.com>
> 
> Hi,
> 
> while currently the sources are release both as .tar.gz and as .tar.bz2 would
> not it be worth to start using .xz as a replacement for the .bz2 variant?
> 
> 13406892 bytes: gdb-6.8.91.20090930.tar.xz  (xz -9)
> xz -dc:    real	0m1.226s user	0m1.190s sys	0m0.037s
> 
> 18453837 bytes: gdb-6.8.91.20090930.tar.bz2
> bzip2 -dc: real	0m3.775s user	0m3.755s sys	0m0.019s

Never heard of it, so my guess it isn't used widely enough yet to make
sense.

Re: xz for the new release tip

[Ralf Corsepius]

On 10/01/2009 08:19 AM, Mark Kettenis wrote:
>> Date: Wed, 30 Sep 2009 22:28:57 +0200
>> From: Jan Kratochvil<jan.kratochvil@redhat.com>
>>
>> Hi,
>>
>> while currently the sources are release both as .tar.gz and as .tar.bz2 would
>> not it be worth to start using .xz as a replacement for the .bz2 variant?
>>
>> 13406892 bytes: gdb-6.8.91.20090930.tar.xz  (xz -9)
>> xz -dc:    real	0m1.226s user	0m1.190s sys	0m0.037s
>>
>> 18453837 bytes: gdb-6.8.91.20090930.tar.bz2
>> bzip2 -dc: real	0m3.775s user	0m3.755s sys	0m0.019s
>
> Never heard of it, so my guess it isn't used widely enough yet to make
> sense.

Well, zz is the successor of lzma.

It's supported as "dist compression" by modern autoconf's 
(autoconf-2.64), it's the internal compression being used in rpm on 
modern Linux distros (Fedora, openSUSE), etc.

Whether it's stable enough and has a longer term perspective is a 
different question or will prove to be a yet another temporary anecdote 
in compression tools is hard to tell - doubts are justified, IMHO.

Ralf

Re: xz for the new release tip

[Ralf Corsepius]

On 10/01/2009 08:27 AM, Ralf Corsepius wrote:
> On 10/01/2009 08:19 AM, Mark Kettenis wrote:
>>> Date: Wed, 30 Sep 2009 22:28:57 +0200
>>> From: Jan Kratochvil<jan.kratochvil@redhat.com>
>>>
>>> Hi,
>>>
>>> while currently the sources are release both as .tar.gz and as
>>> .tar.bz2 would
>>> not it be worth to start using .xz as a replacement for the .bz2
>>> variant?
>>>
>>> 13406892 bytes: gdb-6.8.91.20090930.tar.xz (xz -9)
>>> xz -dc: real 0m1.226s user 0m1.190s sys 0m0.037s
>>>
>>> 18453837 bytes: gdb-6.8.91.20090930.tar.bz2
>>> bzip2 -dc: real 0m3.775s user 0m3.755s sys 0m0.019s
>>
>> Never heard of it, so my guess it isn't used widely enough yet to make
>> sense.
>
> Well, zz is the successor of lzma.
>
> It's supported as "dist compression" by modern autoconf's
> (autoconf-2.64)

Correction: automake (automake-1.11)

, it's the internal compression being used in rpm on
> modern Linux distros (Fedora, openSUSE), etc.
>
> Whether it's stable enough and has a longer term perspective is a
> different question or will prove to be a yet another temporary anecdote
> in compression tools is hard to tell - doubts are justified, IMHO.
>
> Ralf
>
>
>

Re: xz for the new release tip

[Jan Kratochvil]

On Thu, 01 Oct 2009 08:27:12 +0200, Ralf Corsepius wrote:
> it's the internal compression being used in rpm on
> modern Linux distros (Fedora, openSUSE), etc.

I did not think about it to be so fresh, I already got used to it as is it
being pushed for the rpm packaging in Fedora.


> Whether it's stable enough and has a longer term perspective is a
> different question

The file format of current xz-4.999.9beta is already guaranteed to be the one
used in final expectde xz-5.0, specified at:
	http://tukaani.org/xz/format.html


> or will prove to be a yet another temporary anecdote in compression tools is
> hard to tell - doubts are justified, IMHO.

`lzma' is decompressed by `xz' the same way `compress' is decompressed by
`gzip'.  `lzma' was AFAIK already used as the internal format of SuSE rpm so
it already became a format requiring backward compatibility.


I see the xz proposal did not find enough acceptance by GDB maintainers, OK, np.


Regards,
Jan

Re: xz for the new release tip

[Ralf Corsepius]

On 10/01/2009 08:38 AM, Jan Kratochvil wrote:
> On Thu, 01 Oct 2009 08:27:12 +0200, Ralf Corsepius wrote:
>    
>> it's the internal compression being used in rpm on
>> modern Linux distros (Fedora, openSUSE), etc.
>>      
> I did not think about it to be so fresh,
Well, remember the deltarpm on powerpc issue and the "xz occasionly 
corrupts archives on certain files" issues Fedora's xz has (are?) 
suffered from. or will prove to be a yet another temporary anecdote in 
compression tools is
>> hard to tell - doubts are justified, IMHO.
>>      
> `lzma' is decompressed by `xz' the same way `compress' is decompressed by
> `gzip'.  `lzma' was AFAIK already used as the internal format of SuSE rpm so
> it already became a format requiring backward compatibility.
>    
Hmm, from my perspective lzma is one of the "temporary anecdotes" in 
compression history, I am referring to ;)
>
> I see the xz proposal did not find enough acceptance by GDB maintainers, OK, np.
>    
That's a pity. xz compressed gdb-tarballs would have spared rtems.org a 
lot of diskspace and bandwidth ;)

Ralf

Re: xz for the new release tip

[Jan Kratochvil]

On Thu, 01 Oct 2009 08:47:49 +0200, Ralf Corsepius wrote:
> Well, remember the deltarpm on powerpc issue and the "xz occasionly
> corrupts archives on certain files" issues Fedora's xz has (are?)
> suffered from.

http://sourceforge.net/mailarchive/message.php?msg_name=200908272003.48141.lasse.collin%40tukaani.org
[LZMA Utils announce] XZ Utils 4.999.9beta
The most important change is a fix to encoder data corruption bug [...]

Assuming this issue is fortunately gone.


Regards,
Jan