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lrzip (Long Range ZIP or Lzma RZIP) is a file compression program designed
to do particularly well on very large files containing long distance redundancy.

lrztar is a wrapper for lrzip to simplify compression and decompression
of directories. lrzip uses an extended version of rzip which does a first pass
long distance redundancy reduction. The lrzip modifications make it scale
according to memory size. The data is then either:
1. Compressed by lzma (default), zpaq, lzo, gzip or bzip2.
2. Left uncompressed and rzip prepared.

The major disadvantages are:
1. The main lrzip application only works on single files so it requires the
   lrztar wrapper to fake a complete archiver.
2. It requires a lot of memory to get the best performance out of, and is not
   really usable (for compression) with less than 256MB. Decompression requires
   less ram and works on smaller ram machines.
3. It works on stdin/out but in a very inefficient manner generating temporary
   files on disk so this method of using lrzip is not recommended.
4. Files compressed on a 64 bit OS with a compression window greater than 20
   (2 GB) may not decompress on a 32 bit OS.

See the file README.benchmarks for performance examples and what kind of data
lrzip is very good with.