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diff --git a/doc/plzip.info b/doc/plzip.info index 037a286..22f0052 100644 --- a/doc/plzip.info +++ b/doc/plzip.info @@ -12,16 +12,16 @@ File: plzip.info, Node: Top, Next: Introduction, Up: (dir) Plzip Manual ************ -This manual is for Plzip (version 0.6, 20 March 2010). +This manual is for Plzip (version 0.7, 3 December 2010). * Menu: -* Introduction:: Purpose and features of plzip -* Invoking Plzip:: Command line interface -* Program Design:: Internal structure of plzip -* File Format:: Detailed format of the compressed file -* Problems:: Reporting bugs -* Concept Index:: Index of concepts +* Introduction:: Purpose and features of plzip +* Invoking Plzip:: Command line interface +* Program Design:: Internal structure of plzip +* File Format:: Detailed format of the compressed file +* Problems:: Reporting bugs +* Concept Index:: Index of concepts Copyright (C) 2009, 2010 Antonio Diaz Diaz. @@ -36,10 +36,10 @@ File: plzip.info, Node: Introduction, Next: Invoking Plzip, Prev: Top, Up: T ************** Plzip is a massively parallel (multi-threaded), lossless data compressor -based on the LZMA algorithm, with very safe integrity checking and a -user interface similar to the one of gzip or bzip2. Plzip uses the lzip -file format; the files produced by plzip are fully compatible with -lzip-1.4 or newer. +based on the lzlib compression library, with very safe integrity +checking and a user interface similar to the one of bzip2, gzip or lzip. +Plzip uses the lzip file format; the files produced by plzip are fully +compatible with lzip-1.4 or newer. Plzip is intended for faster compression/decompression of big files on multiprocessor machines, which makes it specially well suited for @@ -98,80 +98,80 @@ The format for running plzip is: Plzip supports the following options: -`--help' `-h' +`--help' Print an informative help message describing the options and exit. -`--version' `-V' +`--version' Print the version number of plzip on the standard output and exit. -`--data-size=SIZE' `-B' +`--data-size=SIZE' Set the input data block size in bytes. The input file will be divided in chunks of this size before compression is performed. Valid values range from 8KiB to 1GiB. Default value is two times the dictionary size. Plzip will reduce the dictionary size if it is larger than the chosen data size. -`--stdout' `-c' +`--stdout' Compress or decompress to standard output. Needed when reading from a named pipe (fifo) or from a device. -`--decompress' `-d' +`--decompress' Decompress. -`--force' `-f' +`--force' Force overwrite of output file. -`--keep' `-k' +`--keep' Keep (don't delete) input files during compression or decompression. -`--match-length=LENGTH' `-m LENGTH' +`--match-length=LENGTH' Set the match length limit in bytes. Valid values range from 5 to 273. Larger values usually give better compression ratios but longer compression times. -`--threads=THREADS' `-n THREADS' +`--threads=THREADS' Set the number of worker threads. Valid values range from 1 to "as many as your system can support". If this option is not used, plzip tries to detect the number of processors in the system and use it as default value. -`--output=FILE' `-o FILE' +`--output=FILE' When reading from standard input and `--stdout' has not been specified, use `FILE' as the virtual name of the uncompressed file. This produces a file named `FILE' when decompressing, and a file named `FILE.lz' when compressing. -`--quiet' `-q' +`--quiet' Quiet operation. Suppress all messages. -`--dictionary-size=SIZE' `-s SIZE' +`--dictionary-size=SIZE' Set the dictionary size limit in bytes. Valid values range from 4KiB to 512MiB. Note that dictionary sizes are quantized. If the specified size does not match one of the valid sizes, it will be rounded upwards. -`--test' `-t' +`--test' Check integrity of the specified file(s), but don't decompress them. This really performs a trial decompression and throws away the result. Use `-tvv' or `-tvvv' to see information about the file. -`--verbose' `-v' +`--verbose' Verbose mode. Show the compression ratio for each file processed. Further -v's increase the verbosity level. @@ -180,15 +180,21 @@ The format for running plzip is: limit) as shown in the table below. Note that `-9' can be much slower than `-1'. These options have no effect when decompressing. + The bidimensional parameter space of LZMA can't be mapped to a + linear scale optimal for all files. If your files are large, very + repetitive, etc, you may need to use the `--match-length' and + `--dictionary-size' options directly to achieve optimal + performance. + Level Dictionary size Match length limit - -1 1 MiB 10 bytes - -2 1.5 MiB 12 bytes - -3 2 MiB 17 bytes - -4 3 MiB 26 bytes - -5 4 MiB 44 bytes - -6 8 MiB 80 bytes - -7 16 MiB 108 bytes - -8 24 MiB 163 bytes + -1 1 MiB 5 bytes + -2 1.5 MiB 6 bytes + -3 2 MiB 8 bytes + -4 3 MiB 12 bytes + -5 4 MiB 20 bytes + -6 8 MiB 36 bytes + -7 16 MiB 68 bytes + -8 24 MiB 132 bytes -9 32 MiB 273 bytes `--fast' @@ -328,11 +334,11 @@ Concept Index Tag Table: Node: Top223 -Node: Introduction791 -Node: Invoking Plzip3533 -Node: Program Design7499 -Node: File Format8161 -Node: Problems10117 -Node: Concept Index10646 +Node: Introduction833 +Node: Invoking Plzip3592 +Node: Program Design7840 +Node: File Format8502 +Node: Problems10458 +Node: Concept Index10987 End Tag Table |