[gentoo-user] Compression tools Compared

[gentoo-user] Compression tools Compared

[Jerry McBride]

Anyone else here subscribe to the LINUX JOURNAL?

In the September issue there's a neat article titled tha same as the subject 
line of this message.

The skinny is, there's some really nice file compressors out there and I never 
heard of two of them... Anyone else know about LZMA or 7ZA?

The two mentioned compression tools work pretty much like gzip. You tar up 
your files, pipe to the compression filter and then on to the target file. 
Below is a small example of what I've been seeing here at the shack.

-rw-r--r--  1 root root 12359680 Aug 12 23:57 backup.tar
-rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z
-rw-r--r--  1 root root  4438465 Aug 13 00:08 backup.tar.bz2
-rw-r--r--  1 root root  4747637 Aug 13 00:03 backup.tar.gz
-rw-r--r--  1 root root  2731412 Aug 13 00:10 backup.tar.lzma
-rw-r--r--  1 root root  5125474 Aug 13 00:16 backup.tar.lzop

What you're seeing are the results of compressing /lib on my gentoo powered 
laptop. I've not bothered with timing the processes as the better compression 
rates are at the cost of speed and memory usage. Not good for "while you 
wait" processing, but just plain perfect for backups and what-have-you on 
servers... One side note, 7za does not record user/group info... It's a shame 
too as this make it pretty much useless in most linux backup scenarios. This 
lzma creature is simply awesome.

You can find it at: http://martinus.geekisp.com/rublog.cgi/Projects/LZMA

Cheers all....

-- 

******************************************************************************
                     Registered Linux User Number 185956
              FSF Associate Member number 2340 since 05/20/2004
             Join me in chat at #linux-users on irc.freenode.net
    Buy an Xbox for $149.00, run linux on it and Microsoft loses $150.00!
    12:28am  up 26 days, 27 min,  1 user,  load average: 0.00, 0.00, 0.00
-- 
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Re: [gentoo-user] Compression tools Compared

[Nick Rout]

On Sat, 2005-08-13 at 00:58 -0400, Jerry McBride wrote:
> Anyone else here subscribe to the LINUX JOURNAL?
> 
> In the September issue there's a neat article titled tha same as the subject 
> line of this message.
> 
> The skinny is, there's some really nice file compressors out there and I never 
> heard of two of them... Anyone else know about LZMA or 7ZA?
> 
> The two mentioned compression tools work pretty much like gzip. You tar up 
> your files, pipe to the compression filter and then on to the target file. 
> Below is a small example of what I've been seeing here at the shack.
> 
> -rw-r--r--  1 root root 12359680 Aug 12 23:57 backup.tar
> -rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z
> -rw-r--r--  1 root root  4438465 Aug 13 00:08 backup.tar.bz2
> -rw-r--r--  1 root root  4747637 Aug 13 00:03 backup.tar.gz
> -rw-r--r--  1 root root  2731412 Aug 13 00:10 backup.tar.lzma
> -rw-r--r--  1 root root  5125474 Aug 13 00:16 backup.tar.lzop
> 
> What you're seeing are the results of compressing /lib on my gentoo powered 
> laptop. I've not bothered with timing the processes as the better compression 
> rates are at the cost of speed and memory usage. Not good for "while you 
> wait" processing, but just plain perfect for backups and what-have-you on 
> servers... One side note, 7za does not record user/group info... 


Are you saying it removes user/group info from the tar file?


> It's a shame 
> too as this make it pretty much useless in most linux backup scenarios. This 
> lzma creature is simply awesome.
> 
> You can find it at: http://martinus.geekisp.com/rublog.cgi/Projects/LZMA
> 
> Cheers all....
> 
> -- 
> 
> ******************************************************************************
>                      Registered Linux User Number 185956
>               FSF Associate Member number 2340 since 05/20/2004
>              Join me in chat at #linux-users on irc.freenode.net
>     Buy an Xbox for $149.00, run linux on it and Microsoft loses $150.00!
>     12:28am  up 26 days, 27 min,  1 user,  load average: 0.00, 0.00, 0.00
-- 
Nick Rout <nick@rout.co.nz>

-- 
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Re: [gentoo-user] Compression tools Compared

[Nick Rout]

On Sat, 2005-08-13 at 00:58 -0400, Jerry McBride wrote:
> Anyone else here subscribe to the LINUX JOURNAL?
> 
> In the September issue

errr *grumble* yes but in this part of the world we actually get the
september issue in september, not the start of august!

-- 
Nick Rout <nick@rout.co.nz>

-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] Compression tools Compared

[Fernando Meira]

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Hi,
that lzma is quite impressive!!

Is not my purpose to hijack this topic, but I was wondering if anyone is 
kind enough to give me some comments about linux magazines. I been looking 
into that for some time, but not enough to subscribe one, as I wish to do. I 
know about Linux Journal and Linux Magazine. Both seem good to me. What do 
you subscribe and why is that your preference? 

Cheers,
Fernando

On 8/13/05, Jerry McBride <mcbrides9@comcast.net> wrote:
> 
> 
> Anyone else here subscribe to the LINUX JOURNAL?
> 
> In the September issue there's a neat article titled tha same as the 
> subject
> line of this message.
> 
> The skinny is, there's some really nice file compressors out there and I 
> never
> heard of two of them... Anyone else know about LZMA or 7ZA?
> 
> The two mentioned compression tools work pretty much like gzip. You tar up
> your files, pipe to the compression filter and then on to the target file.
> Below is a small example of what I've been seeing here at the shack.
> 
> -rw-r--r-- 1 root root 12359680 Aug 12 23:57 backup.tar
> -rw-r--r-- 1 root root 3536665 Aug 13 00:01 backup.tar.7z
> -rw-r--r-- 1 root root 4438465 Aug 13 00:08 backup.tar.bz2
> -rw-r--r-- 1 root root 4747637 Aug 13 00:03 backup.tar.gz
> -rw-r--r-- 1 root root 2731412 Aug 13 00:10 backup.tar.lzma
> -rw-r--r-- 1 root root 5125474 Aug 13 00:16 backup.tar.lzop
> 
> What you're seeing are the results of compressing /lib on my gentoo 
> powered
> laptop. I've not bothered with timing the processes as the better 
> compression
> rates are at the cost of speed and memory usage. Not good for "while you
> wait" processing, but just plain perfect for backups and what-have-you on
> servers... One side note, 7za does not record user/group info... It's a 
> shame
> too as this make it pretty much useless in most linux backup scenarios. 
> This
> lzma creature is simply awesome.
> 
> You can find it at: http://martinus.geekisp.com/rublog.cgi/Projects/LZMA
> 
> Cheers all....
> 
> --
> 
> 
> ******************************************************************************
> Registered Linux User Number 185956
> FSF Associate Member number 2340 since 05/20/2004
> Join me in chat at #linux-users on irc.freenode.net<http://irc.freenode.net>
> Buy an Xbox for $149.00, run linux on it and Microsoft loses $150.00!
> 12:28am up 26 days, 27 min, 1 user, load average: 0.00, 0.00, 0.00
> --
> gentoo-user@gentoo.org mailing list
> 
>

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Re: [gentoo-user] Compression tools Compared

[fire-eyes]

On Sat, 2005-08-13 at 12:13 +0000, Fernando Meira wrote:
> Hi,
> that lzma is quite impressive!!

Interesting, there is an .ebuild in the source too ;) It's not in
portage, however.

-- 
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Re: [gentoo-user] Compression tools Compared

[Stephen Micheals]

ive used lzma for a while in windows using 7zip but have not had much
time to test it in linux using p7zip yet. (emerge p7zip)

On 8/13/05, fire-eyes <sgtphou@fire-eyes.org> wrote:
> On Sat, 2005-08-13 at 12:13 +0000, Fernando Meira wrote:
> > Hi,
> > that lzma is quite impressive!!
> 
> Interesting, there is an .ebuild in the source too ;) It's not in
> portage, however.
> 
> --
> gentoo-user@gentoo.org mailing list
> 
>

-- 
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Re: [gentoo-user] Compression tools Compared

[fire-eyes]

On Sat, 2005-08-13 at 05:44 -0700, Stephen Micheals wrote:
> ive used lzma for a while in windows using 7zip but have not had much
> time to test it in linux using p7zip yet. (emerge p7zip)
> 
Sounds like P7 doesn't have the capability to remember user names group
names etc, definately a "i'd try it" killer for me.

-- 
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Re: [gentoo-user] Compression tools Compared

[Jerry McBride]

On Saturday 13 August 2005 01:32 am, Nick Rout wrote:
> On Sat, 2005-08-13 at 00:58 -0400, Jerry McBride wrote:
> > Anyone else here subscribe to the LINUX JOURNAL?
> >
> > In the September issue there's a neat article titled tha same as the
> > subject line of this message.
> >
> > The skinny is, there's some really nice file compressors out there and I
> > never heard of two of them... Anyone else know about LZMA or 7ZA?
> >
> > The two mentioned compression tools work pretty much like gzip. You tar
> > up your files, pipe to the compression filter and then on to the target
> > file. Below is a small example of what I've been seeing here at the
> > shack.
> >
> > -rw-r--r--  1 root root 12359680 Aug 12 23:57 backup.tar
> > -rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z
> > -rw-r--r--  1 root root  4438465 Aug 13 00:08 backup.tar.bz2
> > -rw-r--r--  1 root root  4747637 Aug 13 00:03 backup.tar.gz
> > -rw-r--r--  1 root root  2731412 Aug 13 00:10 backup.tar.lzma
> > -rw-r--r--  1 root root  5125474 Aug 13 00:16 backup.tar.lzop
> >
> > What you're seeing are the results of compressing /lib on my gentoo
> > powered laptop. I've not bothered with timing the processes as the better
> > compression rates are at the cost of speed and memory usage. Not good for
> > "while you wait" processing, but just plain perfect for backups and
> > what-have-you on servers... One side note, 7za does not record user/group
> > info...
>
> Are you saying it removes user/group info from the tar file?
>

Not "removed", it's never put there... :')


-- 

******************************************************************************
                     Registered Linux User Number 185956
              FSF Associate Member number 2340 since 05/20/2004
             Join me in chat at #linux-users on irc.freenode.net
    Buy an Xbox for $149.00, run linux on it and Microsoft loses $150.00!
     9:42am  up 26 days,  9:41,  1 user,  load average: 0.00, 0.00, 0.00
-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] Compression tools Compared

[Zac Medico]

fire-eyes wrote:
> 
> Sounds like P7 doesn't have the capability to remember user names group
> names etc, definately a "i'd try it" killer for me.
> 

If it's anything like gzip or bzip2 then the compression algorithm does not need to support anything like usernames or groups.  That stuff is handled by a separate program such as tar.

Zac
-- 
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Re: [gentoo-user] Compression tools Compared

[Norberto Bensa]

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Jerry McBride wrote:
> One side note, 7za does not record user/group
> info... It's a shame too as this make it pretty much useless in most linux
> backup scenarios. 

So what's the problem? You'll be using something like "tar | 7z" or whatever 
the command for lzma is. I mean, tar handles ownership and permissions. Or am 
I missing something?

-- 
Norberto Bensa
4544-9692 / 15-4190-6344
Ciudad de Buenos Aires, Argentina

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Re: [gentoo-user] Compression tools Compared

[fire-eyes]

On Sat, 2005-08-13 at 11:49 -0300, Norberto Bensa wrote:
> So what's the problem? You'll be using something like "tar | 7z" or
> whatever 
> the command for lzma is. I mean, tar handles ownership and
> permissions. Or am 
> I missing something?

I could be missing something, my brain isn't working right :)

-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] Compression tools Compared

[Nick Rout]

On Sat, 2005-08-13 at 09:36 -0400, Jerry McBride wrote:
> On Saturday 13 August 2005 01:32 am, Nick Rout wrote:
> > On Sat, 2005-08-13 at 00:58 -0400, Jerry McBride wrote:
> > > Anyone else here subscribe to the LINUX JOURNAL?
> > >
> > > In the September issue there's a neat article titled tha same as the
> > > subject line of this message.
> > >
> > > The skinny is, there's some really nice file compressors out there and I
> > > never heard of two of them... Anyone else know about LZMA or 7ZA?
> > >
> > > The two mentioned compression tools work pretty much like gzip. You tar
> > > up your files, pipe to the compression filter and then on to the target
> > > file. Below is a small example of what I've been seeing here at the
> > > shack.
> > >
> > > -rw-r--r--  1 root root 12359680 Aug 12 23:57 backup.tar
> > > -rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z
> > > -rw-r--r--  1 root root  4438465 Aug 13 00:08 backup.tar.bz2
> > > -rw-r--r--  1 root root  4747637 Aug 13 00:03 backup.tar.gz
> > > -rw-r--r--  1 root root  2731412 Aug 13 00:10 backup.tar.lzma
> > > -rw-r--r--  1 root root  5125474 Aug 13 00:16 backup.tar.lzop
> > >
> > > What you're seeing are the results of compressing /lib on my gentoo
> > > powered laptop. I've not bothered with timing the processes as the better
> > > compression rates are at the cost of speed and memory usage. Not good for
> > > "while you wait" processing, but just plain perfect for backups and
> > > what-have-you on servers... One side note, 7za does not record user/group
> > > info...
> >
> > Are you saying it removes user/group info from the tar file?
> >
> 
> Not "removed", it's never put there... :')


I'm sorry but how do you create a tar file without preserving the
usernames and permissions?


> 
> 
> -- 
> 
> ******************************************************************************
>                      Registered Linux User Number 185956
>               FSF Associate Member number 2340 since 05/20/2004
>              Join me in chat at #linux-users on irc.freenode.net
>     Buy an Xbox for $149.00, run linux on it and Microsoft loses $150.00!
>      9:42am  up 26 days,  9:41,  1 user,  load average: 0.00, 0.00, 0.00
-- 
Nick Rout <nick@rout.co.nz>

-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] Compression tools Compared

[Matt Randolph]

Nick Rout wrote:

>On Sat, 2005-08-13 at 09:36 -0400, Jerry McBride wrote:
>  
>
>>On Saturday 13 August 2005 01:32 am, Nick Rout wrote:
>>    
>>
>>>On Sat, 2005-08-13 at 00:58 -0400, Jerry McBride wrote:
>>>      
>>>
>>>>Anyone else here subscribe to the LINUX JOURNAL?
>>>>
>>>>In the September issue there's a neat article titled tha same as the
>>>>subject line of this message.
>>>>
>>>>The skinny is, there's some really nice file compressors out there and I
>>>>never heard of two of them... Anyone else know about LZMA or 7ZA?
>>>>
>>>>The two mentioned compression tools work pretty much like gzip. You tar
>>>>up your files, pipe to the compression filter and then on to the target
>>>>file. Below is a small example of what I've been seeing here at the
>>>>shack.
>>>>
>>>>-rw-r--r--  1 root root 12359680 Aug 12 23:57 backup.tar
>>>>-rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z
>>>>-rw-r--r--  1 root root  4438465 Aug 13 00:08 backup.tar.bz2
>>>>-rw-r--r--  1 root root  4747637 Aug 13 00:03 backup.tar.gz
>>>>-rw-r--r--  1 root root  2731412 Aug 13 00:10 backup.tar.lzma
>>>>-rw-r--r--  1 root root  5125474 Aug 13 00:16 backup.tar.lzop
>>>>
>>>>What you're seeing are the results of compressing /lib on my gentoo
>>>>powered laptop. I've not bothered with timing the processes as the better
>>>>compression rates are at the cost of speed and memory usage. Not good for
>>>>"while you wait" processing, but just plain perfect for backups and
>>>>what-have-you on servers... One side note, 7za does not record user/group
>>>>info...
>>>>        
>>>>
>>>Are you saying it removes user/group info from the tar file?
>>>
>>>      
>>>
>>Not "removed", it's never put there... :')
>>    
>>
>
>
>I'm sorry but how do you create a tar file without preserving the
>usernames and permissions?
>
>  
>

This may be a case of a different paradigm being used by 7-zip than that 
used by traditional (*nix) compression tools.  If my memory serves me, 
the 7-zip format is very similar to the pkzip format in its usage.  By 
that I mean that one is not required to make a tarball before 
compressing multiple files.  The format allows you to skip the tar step 
and make an archive consisting of whichever files and directories you wish.

The problem, I'm guessing, is that the 7-zip archive format was 
developed in the Windows world where users and groups and permissions 
have no meaning (I think that has changed or is changing in the NT/XP 
world, but I don't know and don't especially care).  Hence, these 
attributes aren't accomodated by this format.  I assume the 7-zip 
extractor program sets the user and group of the extracted files to that 
of whomever extracts them.

What everyone has rightly pointed out, namely that you can make a 
tarball and then compress that, is exactly right.  That IS how one would 
use 7-zip with a proper operating system.

The original poster most likely used the 7-zip archiver as a stand-alone 
tool, rather than using it in conjunction with tar.  This is not 
altogether surprising as one typically compresses a directory with a 
single tar command (and an implied pipe) rather than explicitly piping 
the output of tar to the compression utility.  Since there is no --7-zip 
switch in tar, the OP couldn't simply 'tar -7cf backup.tar.7zip lib/'.  
The OP probably simply 7-zipped his directory without tarring it first 
and consequently ran into the limitations of the archive format.

-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] Compression tools Compared

[Matt Randolph]

Matt Randolph wrote:

> Nick Rout wrote:
>
>> On Sat, 2005-08-13 at 09:36 -0400, Jerry McBride wrote:
>>  
>>
>>> On Saturday 13 August 2005 01:32 am, Nick Rout wrote:
>>>   
>>>
>>>> On Sat, 2005-08-13 at 00:58 -0400, Jerry McBride wrote:
>>>>     
>>>>
>>>>> Anyone else here subscribe to the LINUX JOURNAL?
>>>>>
>>>>> In the September issue there's a neat article titled tha same as the
>>>>> subject line of this message.
>>>>>
>>>>> The skinny is, there's some really nice file compressors out there 
>>>>> and I
>>>>> never heard of two of them... Anyone else know about LZMA or 7ZA?
>>>>>
>>>>> The two mentioned compression tools work pretty much like gzip. 
>>>>> You tar
>>>>> up your files, pipe to the compression filter and then on to the 
>>>>> target
>>>>> file. Below is a small example of what I've been seeing here at the
>>>>> shack.
>>>>>
>>>>> -rw-r--r--  1 root root 12359680 Aug 12 23:57 backup.tar
>>>>> -rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z
>>>>> -rw-r--r--  1 root root  4438465 Aug 13 00:08 backup.tar.bz2
>>>>> -rw-r--r--  1 root root  4747637 Aug 13 00:03 backup.tar.gz
>>>>> -rw-r--r--  1 root root  2731412 Aug 13 00:10 backup.tar.lzma
>>>>> -rw-r--r--  1 root root  5125474 Aug 13 00:16 backup.tar.lzop
>>>>>
>>>>> What you're seeing are the results of compressing /lib on my gentoo
>>>>> powered laptop. I've not bothered with timing the processes as the 
>>>>> better
>>>>> compression rates are at the cost of speed and memory usage. Not 
>>>>> good for
>>>>> "while you wait" processing, but just plain perfect for backups and
>>>>> what-have-you on servers... One side note, 7za does not record 
>>>>> user/group
>>>>> info...
>>>>>       
>>>>
>>>> Are you saying it removes user/group info from the tar file?
>>>>
>>>>     
>>>
>>> Not "removed", it's never put there... :')
>>>   
>>
>>
>>
>> I'm sorry but how do you create a tar file without preserving the
>> usernames and permissions?
>>
>>  
>>
>
> This may be a case of a different paradigm being used by 7-zip than 
> that used by traditional (*nix) compression tools.  If my memory 
> serves me, the 7-zip format is very similar to the pkzip format in its 
> usage.  By that I mean that one is not required to make a tarball 
> before compressing multiple files.  The format allows you to skip the 
> tar step and make an archive consisting of whichever files and 
> directories you wish.
>
> The problem, I'm guessing, is that the 7-zip archive format was 
> developed in the Windows world where users and groups and permissions 
> have no meaning (I think that has changed or is changing in the NT/XP 
> world, but I don't know and don't especially care).  Hence, these 
> attributes aren't accomodated by this format.  I assume the 7-zip 
> extractor program sets the user and group of the extracted files to 
> that of whomever extracts them.
>
> What everyone has rightly pointed out, namely that you can make a 
> tarball and then compress that, is exactly right.  That IS how one 
> would use 7-zip with a proper operating system.
>
> The original poster most likely used the 7-zip archiver as a 
> stand-alone tool, rather than using it in conjunction with tar.  This 
> is not altogether surprising as one typically compresses a directory 
> with a single tar command (and an implied pipe) rather than explicitly 
> piping the output of tar to the compression utility.  Since there is 
> no --7-zip switch in tar, the OP couldn't simply 'tar -7cf 
> backup.tar.7zip lib/'.  The OP probably simply 7-zipped his directory 
> without tarring it first and consequently ran into the limitations of 
> the archive format.
>
"-rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z"

Oops!  I should read more carefully.

-- 
"Pluralitas non est ponenda sine necessitate" - W. of O.

-- 
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Re: [gentoo-user] Compression tools Compared

[Matt Randolph]

Matt Randolph wrote:

> Matt Randolph wrote:
>
>>
>> This may be a case of a different paradigm being used by 7-zip than 
>> that used by traditional (*nix) compression tools.  If my memory 
>> serves me, the 7-zip format is very similar to the pkzip format in 
>> its usage.  By that I mean that one is not required to make a tarball 
>> before compressing multiple files.  The format allows you to skip the 
>> tar step and make an archive consisting of whichever files and 
>> directories you wish.
>>
>> The problem, I'm guessing, is that the 7-zip archive format was 
>> developed in the Windows world where users and groups and permissions 
>> have no meaning (I think that has changed or is changing in the NT/XP 
>> world, but I don't know and don't especially care).  Hence, these 
>> attributes aren't accomodated by this format.  I assume the 7-zip 
>> extractor program sets the user and group of the extracted files to 
>> that of whomever extracts them.
>>
>> What everyone has rightly pointed out, namely that you can make a 
>> tarball and then compress that, is exactly right.  That IS how one 
>> would use 7-zip with a proper operating system.
>>
>> The original poster most likely used the 7-zip archiver as a 
>> stand-alone tool, rather than using it in conjunction with tar.  This 
>> is not altogether surprising as one typically compresses a directory 
>> with a single tar command (and an implied pipe) rather than 
>> explicitly piping the output of tar to the compression utility.  
>> Since there is no --7-zip switch in tar, the OP couldn't simply 'tar 
>> -7cf backup.tar.7zip lib/'.  The OP probably simply 7-zipped his 
>> directory without tarring it first and consequently ran into the 
>> limitations of the archive format.
>>
> "-rw-r--r--  1 root root  3536665 Aug 13 00:01 backup.tar.7z"
>
> Oops!  I should read more carefully.
>

In an effort to put this matter to rest (and to save a little face), I 
have tested 7-zip.

I created a directory containing two empty files.  These files were then 
assigned arbitrary users and groups.  Next I created a tarball of the 
directory.  I changed the ownership of the tarball too.  Finally, I 
7-zipped the tarball. 

When I extracted the tarball it was given the user and group of the 
extractor (eg. myusername:users) rather than what it was assigned 
above.  When I untarred the tarball, however, the contents were exactly 
as you would expect; they had the user and group settings that I 
assigned them previously.

I once again feel that my original hypothesis is essentially correct.  
7-zip doesn't support user, group and permission data because it was 
originally developed for Windows.  But this is a limitation that can be 
worked around by making a tarball first.  The OP noticed that the 
ownership and permissions of the tarball changed and made a comment 
about that.  This fact has little relevance for most users since we will 
only care about the contents of the tarball, not the tarball itself.

-- 
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Re: [gentoo-user] Compression tools Compared

[Neil Bothwick]

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On Wed, 17 Aug 2005 00:53:05 -0400, Matt Randolph wrote:

> In an effort to put this matter to rest (and to save a little face), I 
> have tested 7-zip.

Or you could have read the README that covers this in some details. It
not only says that you should use tar to preserve ownership and
permissions but also gives the commands needed :)

I tried p7zip last night, on a 2GB VMWare disk image, and the compressed
file was 10% smaller than rzip gave, which was the best compressor I'd
found to date.


-- 
Neil Bothwick

... but you can't expect to wield supreme executive power just because
some watery tart threw a sword at you!

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Re: [gentoo-user] Compression tools Compared

[Kirk Strauser]

On Friday 12 August 2005 23:58, Jerry McBride wrote:

> What you're seeing are the results of compressing /lib on my gentoo
> powered laptop.

For comparison purposes, what compression levels did you specify for bz2 and 
gz?
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Kirk Strauser
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Re: [gentoo-user] Compression tools Compared

[Jerry McBride]

On Wednesday 17 August 2005 10:55 am, Kirk Strauser wrote:
> On Friday 12 August 2005 23:58, Jerry McBride wrote:
> > What you're seeing are the results of compressing /lib on my gentoo
> > powered laptop.
>
> For comparison purposes, what compression levels did you specify for bz2
> and gz?
> --
> Kirk Strauser

hi Kirk,

It's been a couple of days, but I do believe I used -9 and -9....

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