rzip vs. bzip2 – A short comparison

I decided to benchmark rzip against bzip for my backup needs. The benchmark was performed on a 89M tar archive of a directory which I regularly backup using my Amazon S3 backup script. The directory contains mostly LaTeX, PDF and Open Office files, so this benchmark may reflect very different results than what you will get if you will test it on other kinds of files.

I ran both rzip and bzip with their default settings. bzip, the program I currently use for my backups, managed to compress the tar file to 43.5M in 1:4.286 (min:sec). On the other hand, rzip compressed the tar into a mere 39M and did in only 32.844 seconds.

When weighting the results based only on the resulted compressed file and processing time, rzip takes bzip by far. It has superior compressing abilities and rzip does it two times faster than bzip.

One must note that rzip was much more memory intensive, so it isn’t suited for environments which are low on available memory. Another disadvantage of rzip is that it can’t operate on stdin/stdout, so one must first physically create the file on the disk before compressing it.

As I don’t have any memory shortage on my machine (especially during the night when I make my backups), and I can live with creating a temporary tar file, I plan to switch over my backup script to use rzip. The new script will probably work very similar to the current one except it will produce a rzip compressed archive, which will help me cut down the costs of backups.