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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.