I tried to benchmark a little. Archivers were limited to 512 Mb. Timings only in the second test. Precision is kept 1 Mb/10 seconds intentionally.

There are many comprehensive benchmarks, but I tested nearly the last versions.

OpenOffice 2.0.2 sources, 1209 Mb (there are several .gz and other binary files inside). (RAR and 7z had the advantage of managing files themselves to create "solid" archives, gzip and bzip2 were used on a 1209 Mb "ball" made by RAR.)

Rar (3.60 beta 2):  212 Mb
gzip (1.2.4):       276 Mb
bzip2 (1.0.3):      230 Mb
7z PPMd (4.4.2):    190 Mb
7z LZMA (--""--):   too slow (~100 Kb/s, more than three hours)

After that I tried to compress FPC SVN (153 Mb), and the numbers were in different order (FPC "ball" was created in 2 minutes by Rar):

Rar     21 Mb  5 minutes
gzip    29 Mb  1 minute 30 seconds
bzip2   20 Mb  3 minutes 40 seconds (is it optimized for pascal?)
7z PPMd 17 Mb  8 minutes 20 seconds
7z LZMA 16 Mb 25 minutes (well, it would be better, I believe it had memory problems)

I tried PPMonster archiver (open source, from the author of PPMd algorithm), while sources are less than 60 Kb in C, speed is often about 20 Kb/s. However, it promised 0.548 bits per byte of the FPC "ball" (but >1.5 for OpenOffice).

Then try one of the last compressors as PAQ8, your OO 2.0.2 sources will take days in compress, but i think you can get 140-150 MB or even less and is opensource too. But it isn't used out of comp.compression world. Also, the WinRK3.03 is a lot faster and gets a bit more compression, but only works on windows. The tar.gz of FreeBSD (90MB decompressed) goes to 12 MB with medium compression, but takes 20 min in a 2GHz Athlon. Check http://www.maximumcompression.com/ for details and the newsgroup comp.compression or datacompression.info for more info.

Just change the gzip to a better zip program for make zip files, as 7z, and you'll get an improvement from current compression, but the bzip2 suggestion is very good, even FreeBSD has changed the tar.gz system to tar.bz2 (tbz) and the difference is notable.


A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
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