ckolivas / lrzip

Long Range Zip
http://lrzip.kolivas.org
GNU General Public License v2.0
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lower compression than in previous versions #191

Closed Toutatis2 closed 3 years ago

Toutatis2 commented 3 years ago

I am using lrzip-0.640 on slackware64-current. I have a file compressed a some time ago with an older version of lrzip

lrzip -i FreeCAD-0-17.tar.lrz FreeCAD-0-17.tar.lrz: lrzip version: 0.6 file Compression: rzip + lzma Decompressed file size: 385034240 Compressed file size: 174120138 Compression ratio: 2.211 MD5 used for integrity testing MD5: 657e693a4007a6b5dafa893118c362d4

I uncompress it, and recompress using lrzip version 0.640:

lrzip FreeCAD-0-17.tar Output filename is: FreeCAD-0-17.tar.lrz FreeCAD-0-17.tar - Compression Ratio: 1.474. Average Compression Speed: 61.167MB/s. Total time: 00:00:06.40

The compress ratio falls from 2.211 to 1.474

lrzip -i FreeCAD-0-17.tar.lrz FreeCAD-0-17.tar.lrz: lrzip version: 0.6 file Compression: rzip + lzma Decompressed file size: 385034240 Compressed file size: 261303125 Compression ratio: 1.474 MD5 used for integrity testing MD5: 657e693a4007a6b5dafa893118c362d4

Now I try with the maximum compression (zpaq):

lrzip -z FreeCAD-0-17.tar Output filename is: FreeCAD-0-17.tar.lrz Total: 99% Chunk: 99% ZPAQ 7:0% 8:0% ZPAQ 7:10% ZPAQ 7:20% ZPAQ 8:10% ZPAQ 7:30% ZPAQ 7:40% ZPAQ 8:20% ZPAQ 7:50% ZPAQ 7:60% ZPAQ 8:30% ZPAQ 7:70% ZPAQ 7:80% ZPAQ 8:40% ZPAQ 7:90% ZPAQ 8:50% ZPAQ 7:100% ZPAQ 8:60% ZPAQ 8:70% ZPAQ 8:80% ZPAQ 8:90% ZPAQ 8FreeCAD-0-17.tar - Compression Ratio: 1.477. Average Compression Speed: 28.231MB/s. Total time: 00:00:12.52

The compression ratio is only a little better

lrzip -i FreeCAD-0-17.tar.lrz FreeCAD-0-17.tar.lrz: lrzip version: 0.6 file Compression: rzip + zpaq Decompressed file size: 385034240 Compressed file size: 260763791 Compression ratio: 1.477 MD5 used for integrity testing MD5: 657e693a4007a6b5dafa893118c362d4

ckolivas commented 3 years ago

There is already a newer version that addresses this.