Bzip2 is a very slow compression algorithm, mostly due, from what I recall, to the Burrows-Wheeler transform that lies at its core. LZMA is pretty much superio

Bzip2 is a very slow compression algorithm, mostly due, from what I recall, to the Burrows-Wheeler transform that lies at its core. LZMA is pretty much superior in every respect; it is (though quite slowly) on the road to replacing the aging Bzip2. And as usual the comments on CodingHorror (at least the initial dozen or two) show a relative ignorance about the topic. 7zip (as can any compressor) can be trivially parallelized just by running it simultaneously on each solid block. The compression cost of a smaller solid block size is generally near-zero for the case where dictionary size << input data size. The included Windows interface doesn't allow this kind of threading AFAIK, but it would be relatively simple to implement in an app using the LZMA libraries.