From owner-freebsd-hackers@FreeBSD.ORG  Tue Feb 26 18:45:08 2008
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Date: Tue, 26 Feb 2008 19:44:48 +0100
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Subject: Re: emulate an end-of-media
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Hi,

> Yes, gzip or bzip2 compress better, but they also:
>   * Are a lot slower.

Yesterday I made a comparison regarding the speed
of compress, bzip2 and gzip.
And actually compress is much slower than gzip:


$ dd if=3D/dev/random |compress -c > /dev/null
3883204 bytes/sec
$ dd if=3D/dev/random |gzip -c > /dev/null
8357889 bytes/sec
$ dd if=3D/dev/random |bzip2 -c > /dev/null
1042735 bytes/sec

I also made a comparison between gzip and bzip2 regarding
the compression ratio on a dump of my home directory (3.2GB)
bzip2 took about 74min to compress, gzip only 11minutes. And
in terms of compression ratio bzip2 was only 3% better than
gzip.

Best greet,
   Martin L.