bzip2 and gzip internals

[Phillip Susi]

Paul Sladen wrote:

>>>The data stream DOESN'T restart every 900 KB,
>>>      
>>>
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>The advantage of Free Software is that you get the source code...
>
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>

Not sure what your point was with that. 

>>>That's what gzip --rsyncable does,
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>>>
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>"--rsync" resets the gzip stream everytime the rolling checksum equals zero,
>as such it is not a fixed period.
>
>  
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I do not believe that is the case.  As I understand it, --rsyncable just 
causes gzip to stop and restart compressing every x KB.  This produces 
the same result as spliting the source file into blocks of x KB, 
gzipping each one individually, then concatenating all of those.  The 
benefit to this is that a single changed byte in the uncompressed stream 
will at most, change x KB in the compressed stream.  The disadvantage is 
that you get even lower compression.