tarring a dump. Problems with a pipe

[Gary W. Swearingen]

Robin Smith <rasmith at aristotle.tamu.edu> writes:

> dump -0 -f - /dev/yourfilesystem |bzip2 -c >dump.bz

I compressed a filesystem dump (on Athlon 64/3200+, i386 OS) and

    bzip2  compressed to 50% of 2 GB in 1118 sec 
    gzip   compressed to 52% of 2 GB in  306 sec

But bzip2 can compress much better than that on some stuff.

If your goal is a small backup, bzip compresses better.
If your goal is a quick backup to disk, gzip is faster.
If your goal is a quick backup to tape, bzip is faster
   because tape is so slow, unless your CPU can't keep up.