[avar]

I tried it on a 943M tarball that contains miscellaneous Git repositories and their checked out trees that I had lying around:

    Compressor  Size  Ratio  Compression  Decompression
    gzip -9     555M  59%    2m39.840s    0m16.495s
    bzip2 -9    531M  56%    4m10.541s    1m27.720s
    xz -9       457M  48%    13m55.730s   0m53.290s

[rntz]

Testing them all on -9 is perhaps not a fair comparison. For example, according to http://changelog.complete.org/archives/931-how-to-think-abou..., gzip -9 saved a tiny amount of space compared to gzip's default, but took significantly longer.