Bzip2 vs Gzip & some thoughts.

Mr. James W. Laferriere Network Engineer (babydr@nwrain.net)
Mon, 15 Dec 1997 00:15:11 -0800 (PST)


Hello All, I started with a gcc-2.7.2.1.tar ball for
a resonably large example. And here is what I got.

ls -l *.tar*
-rw-r--r-- 1 root root 28211200 Dec 14 22:54 gcc-test.tar1
-rw-r--r-- 1 root root 28211200 Dec 14 22:55 gcc-test.tar2

/usr/bin/time -o bzip2.test --append bzip2 gcc-test.tar1
208.65user 1.83system 3:54.24elapsed 89%CPU
(0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (6632major+1632minor)pagefaults 0swaps
ls -l *.tar*
-rw-r--r-- 1 root root 5303302 Dec 14 22:54 gcc-test.tar1.bz2
-rw-r--r-- 1 root root 28211200 Dec 14 22:55 gcc-test.tar2

/usr/bin/time -o bzip2.test --append gzip gcc-test.tar2
86.58user 2.14system 1:39.40elapsed 89%CPU
(0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (6971major+89minor)pagefaults 0swaps
ls -l *.tar*
-rw-r--r-- 1 root root 5303302 Dec 14 22:54 gcc-test.tar1.bz2
-rw-r--r-- 1 root root 7132305 Dec 14 22:55 gcc-test.tar2.gz

/usr/bin/time -o bzip2.test --append bunzip2 gcc-test.tar1.bz2
50.62user 3.00system 1:02.76elapsed 85%CPU
(0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (1370major+1127minor)pagefaults 0swaps
ls -l *.tar*
-rw-r--r-- 1 root root 28211200 Dec 14 22:54 gcc-test.tar1
-rw-r--r-- 1 root root 7132305 Dec 14 22:55 gcc-test.tar2.gz

/usr/bin/time -o bzip2.test --append gunzip gcc-test.tar2.gz
8.02user 2.47system 0:16.14elapsed 64%CPU
(0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (1816major+34minor)pagefaults 0swaps
ls -l *.tar*
-rw-r--r-- 1 root root 28211200 Dec 14 22:54 gcc-test.tar1
-rw-r--r-- 1 root root 28211200 Dec 14 22:55 gcc-test.tar2

Original size / Bzip2 (compressed) = 5.319553
Compressing 208.65user 1.83system 3:54.24elapsed 89%CPU
UnCompressing 50.62user 3.00system 1:02.76elapsed 85%CPU
Compressing Elapsed = 234.24 sec
UnCompressing Elapsed = 62.76 sec

Original size / Gzip (compressed) = 3.955411
Compressing 86.58user 2.14system 1:39.40elapsed 89%CPU
UnCompressing 8.02user 2.47system 0:16.14elapsed 64%CPU
Compressing Elapsed = 99.40 sec
UnCompressing Elapsed = 16.14 sec

1.344879 = 134.4879 % better compression. ( Nice :-)
But takes 2.356539 times longer to achieve this. (:-})
And takes 3.888475 times longer to UnCompress than gzip. (:-})

AMD5k86-p90, 64MB Mem(60ns)

Tia, JimL
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| James W. Laferriere - Network Engineer - babydr@nwrain.net |
| System Techniques - 25416 - 22nd S. - Kent, WA 98032 |
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