Recently, I've been busy preparing various directories for additional archiving in Linux (it's about files from the /var/log/ location) containing archives of reports of performed operations in the system and running programs (services such as www etc.). Since I often use archiving to RAR format, I decided to see if it would work in this case as well.
I performed the test on Debian 11 (Linux kernel 5.10.0-13-amd64), on a system with 2 Xeon E5-2630L v2 processors, equipped with 64GB of RAM and an SSD (SATA) drive.
First, I created a tar archive of the entire /var/log directory using the command "time tar -pcf log.tar /var/log". The created archive occupies 1.7GB on the disk. Below are the results done with these commands:
rar archiving (registered v 6.12, from the manufacturer's website): time rar a -m5 -ma5 -md64m -mt24 -r /log.rar /log.tar
bzip2 archiving (v 1.0.8, installed with apt): time bzip2 -k -z -9 log.tar
lbzip2 archiving (v 2.5, installed with apt): time lbzip2 -k -z -9 log.tar
The time command allows you to determine the amount of time the command used to run. Here are the results:
| Archive (file name) | Archive creation time (seconds) | File size (KB) |
| log.tar | 2,64 | 1758197 |
| log.rar | 36,87 | 276366 |
| log.tar.bz2 (bzip2) | 313,06 | 275410 |
| log.tar.bz2 (Lbzip2) | 7,83 | 274947 |
As you can see, the best performance is in archiving to a bz2 file, using lbzip2 (which is a bzip2 implementation capable of using multiple cores, hence the big speedup).