Overhaul documentation part #1
Detect and handle uncompressed PDF files using libbsc. Force binary/text data detection for tar archives. Get rid of unnecessary CLI option. Add full pipeline mode check when archiving.
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README.md
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README.md
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@ -6,31 +6,32 @@ Use is subject to license terms.
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moinakg (_at) gma1l _dot com.
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Comments, suggestions, code, rants etc are welcome.
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Pcompress is a utility to do compression and decompression in parallel by
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splitting input data into chunks. It has a modular structure and includes
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support for multiple algorithms like LZMA, Bzip2, PPMD, etc, with SKEIN/
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SHA checksums for data integrity. It can also do Lempel-Ziv pre-compression
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(derived from libbsc) to improve compression ratios across the board. SSE
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optimizations for the bundled LZMA are included. It also implements
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Variable Block Deduplication and Delta Compression features based on a
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Semi-Rabin Fingerprinting scheme. Delta Compression is done via the widely
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popular bsdiff algorithm. Similarity is detected using a technique based
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on MinHashing. When doing Dedupe it attempts to merge adjacent non-
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duplicate block index entries into a single larger entry to reduce metadata.
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In addition to all these it can internally split chunks at rabin boundaries
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to help Dedupe and compression.
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Pcompress is an archiver that also does compression and decompression in
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parallel by splitting input data into chunks. It has a modular structure
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and includes support for multiple algorithms like LZMA, Bzip2, PPMD, etc,
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with SKEIN/SHA checksums for data integrity. Compression algorithms are
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selected based on the file type to maximize compression gains using a file
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and data anaylis based adaptive technique. It also includes various data
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transformation filters to improve compression.
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It also implements Variable Block Deduplication and Delta Compression
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features based on a Polynomial Fingerprinting scheme. Delta Compression
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is done via the widely popular bsdiff algorithm. Similarity is detected
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using a technique based on MinHashing. Deduplication metadata is also
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compressed to reduce overheads. In addition to all these it can internally
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split chunks at file and rabin boundaries to help Dedupe and compression.
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It has low metadata overhead and overlaps I/O and compression to achieve
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maximum parallelism. It also bundles a simple slab allocator to speed
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repeated allocation of similar chunks. It can work in pipe mode, reading
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from stdin and writing to stdout. It also provides adaptive compression
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modes in which data analysis heuristics are used to identify near-optimal
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algorithms per chunk. Finally it supports 14 compression levels to allow
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for ultra compression parameters in some algorithms.
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from stdin and writing to stdout. SIMD vector optimizations using the x86
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SSE instruction set are used to speed up various operations. Finally it
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supports 14 compression levels to allow for ultra compression parameters
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in some algorithms.
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Pcompress also supports encryption via AES and uses Scrypt from Tarsnap
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for Password Based Key generation. A unique key is generated per session
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even if the same password is used and HMAC is used to do authentication.
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Pcompress also supports encryption via AES, Salsa20 and uses Scrypt from
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Tarsnap for Password Based Key generation. A unique key is generated per
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session even if the same password is used and HMAC is used to do authentication.
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Links of Interest
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=================
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@ -49,59 +50,229 @@ http://moinakg.wordpress.com/2013/06/11/architecture-for-a-deduplicated-archival
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http://moinakg.wordpress.com/2013/06/15/architecture-for-a-deduplicated-archival-store-part-2/
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Usage
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=====
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Standard Usage
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==============
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Standard usage consists of a few common options to control basic behavior. A variety of
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parameters including global deduplication are automatically set based on the compression
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level.
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To compress a file:
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pcompress -c <algorithm> [-l <compress level>] [-s <chunk size>] <file> [<target file>]
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Archiving
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---------
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pcompress -a [-v] [-l <compress level>] [-s <chunk size>] [-c <algorithm>]
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[<file1> <directory1> <file2> ...] [-t <number>] [-S <chunk checksum>]
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<archive filename or '-'>
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Where <algorithm> can be the folowing:
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lzfx - Very fast and small algorithm based on LZF.
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lz4 - Ultra fast, high-throughput algorithm reaching RAM B/W at level1.
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zlib - The base Zlib format compression (not Gzip).
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lzma - The LZMA (Lempel-Ziv Markov) algorithm from 7Zip.
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lzmaMt - Multithreaded version of LZMA. This is a faster version but
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uses more memory for the dictionary. Thread count is balanced
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between chunk processing threads and algorithm threads.
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bzip2 - Bzip2 Algorithm from libbzip2.
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ppmd - The PPMd algorithm excellent for textual data. PPMd requires
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Archives a given set of files and/or directories into a compressed PAX archive. The
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PAX datastream is encoded into a custom format compressed file that can only be
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handled by Pcompress.
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-a Enables archive mode where pathnames specified in the command line are
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archived using LibArchive and then compressed.
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-l <compress level>
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Select a compression level from 1 (least compression, fastest) to 14
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(ultra compression, slow). Default: 6
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-s <chunk size>
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Archive data is split into chunks that are processed in parallel. This value
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specifies the maximum chunk size. Blocks may be smaller than this. Values
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can be in bytes or <number><suffix> format where suffix can be k - KB, m - MB,
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g - GB. Default: 8m
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Larger chunks can produce better compression at the cost of memory.
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-c <algorithm>
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Specifies the compression algorithm to use. Default algorithm when archiving
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is adapt2 (Second Adaptive Mode). This is the ideal mode for archiving giving
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best compression gains. However adapt (Adaptive Mode) can be used which is a
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little faster but give lower compression gains.
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Other algorithms can be used if all the files are of the same known type. For
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example ppmd (slow) or libbsc (fast) can be used if all the files only have
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ASCII text. See section "Compression Algorithms" for details.
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-v Enables verbose mode where each file/directory is printed as it is processed.
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-t <number>
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Sets the number of threads that Pcompress can use. Pcompress automatically
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uses thread count = core count. However with larger chunk size (-s option)
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and/or ultra compression levels, large amounts of memory can be used. In this
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case thread count can be reduced to reduce memory consumption.
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-S <chunk checksum>
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Specify then chunk checksum to use. Default: BLAKE256. The following checksums
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are available:
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CRC64 - Extremely Fast 64-bit CRC from LZMA SDK.
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SHA256 - SHA512/256 version of Intel's optimized (SSE,AVX) SHA2 for x86.
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SHA512 - SHA512 version of Intel's optimized (SSE,AVX) SHA2 for x86.
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KECCAK256 - Official 256-bit NIST SHA3 optimized implementation.
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KECCAK512 - Official 512-bit NIST SHA3 optimized implementation.
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BLAKE256 - Very fast 256-bit BLAKE2, derived from the NIST SHA3
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runner-up BLAKE.
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BLAKE512 - Very fast 256-bit BLAKE2, derived from the NIST SHA3
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runner-up BLAKE.
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The fastest checksum is the BLAKE2 family.
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<archive filename>
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Pathname of the resulting archive. A '.pz' extension is automatically added
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if not already present. This can also be specified as '-' in order to send
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the compressed archive stream to stdout.
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Single File Compression
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-----------------------
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pcompress -c <algorithm> [-l <compress level>] [-s <chunk size>] [-p] [<file>]
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[-t <number>] [-S <chunk checksum>] [<target file or '-'>]
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Takes a single file as input and produces a compressed file. Archiving is not performed.
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This can also work as compression pipeline.
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-c <algorithm>
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See above. Also see section "Compression Algorithms" for details.
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-l <compress level>
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-s <chunk size>
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-t <number>
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-S <chunk checksum>
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See above.
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Note: In singe file compression mode with adapt2 or adapt algorithm, larger
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chunks may not produce better compression. Smaller chunks can result
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in better data analysis here.
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-p Make Pcompress work in full pipeline mode. Data is ingested via stdin
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compressed and output via stdout. No filenames are used.
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<target file>
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Pathname of the compressed file to be created. This can be '-' to send the
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compressed data to stdout.
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Decompression and Archive extraction
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------------------------------------
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pcompress -d <compressed file or '-'> [-m] [-K] [<target file or directory>]
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-m Enable restoring *all* permissions, ACLs, Extended Attributes etc.
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Equivalent to the '-p' option in tar. Ownership is only extracted if run as
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root user.
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-K Do not overwrite newer files.
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-m and -K are only meaningful if the compressed file is an archive. For single file
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compressed mode these options are ignored.
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<compressed file>
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Specifies the compressed file or archive. This can be '-' to indicate reading
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from stdin while write goes to <target file>
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<target file or directory>
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This can be a filename or a directory depending on how the archive was created.
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If single file compression was used then this can be the name of the target
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file that will hold the uncompressed data.
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If this is omitted then an output file is created by appending '.out' to the
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compressed filename.
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If Archiving was done then this should be the name of a directory into which
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extracted files are restored. The directory is created if it does not exist.
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If this is omitted the files are extracted into the current directory.
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Compression Algorithms
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======================
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lzfx - Fast, average compression. At high compression levels this can be faster
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than LZ4.
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Effective Levels: 1 - 5
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lz4 - Very Fast, sometimes better compression than LZFX.
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Effective Levels: 1 - 3
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zlib - Fast, better compression.
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Effective Levels: 1 - 9
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bzip2 - Slow, much better compression than Zlib.
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Effective Levels: 1 - 9
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lzma - Very slow. Extreme compression. Recommended: Use lzmaMt variant mentioned
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below.
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Effective Levels: 1 - 14
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Till level 9 it is standard LZMA parameters. Levels 10 - 12 use
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more memory and higher match iterations so are slower. Levels
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13 and 14 use larger dictionaries upto 256MB and really suck up
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RAM. Use these levels only if you have at the minimum 4GB RAM on
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your system.
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lzmaMt - This is the multithreaded variant of lzma and typically runs faster.
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However in a few cases this can produce slightly lesser compression
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gain.
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PPMD - Slow. Extreme compression for Text, average compression for binary.
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In addition PPMD decompression time is also high for large chunks.
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This requires lots of RAM similar to LZMA. PPMd requires
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at least 64MB X core-count more memory than the other modes.
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Effective Levels: 1 - 14.
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libbsc - A Block Sorting Compressor using the Burrows Wheeler Transform
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like Bzip2 but runs faster and gives better compression than
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Bzip2 (See: libbsc.com).
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Adapt - Synthetic mode with text/binary detection. For pure text data PPMD is
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used otherwise Bzip2 is selected per chunk.
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Effective Levels: 1 - 14
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Adapt2 - Slower synthetic mode. For pure text data PPMD is otherwise LZMA is
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applied. Can give very good compression ratio when splitting file
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into multiple chunks.
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Effective Levels: 1 - 14
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Since both LZMA and PPMD are used together memory requirements are
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large especially if you are also using extreme levels above 10. For
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example with 100MB chunks, Level 14, 2 threads and with or without
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dedupe, it uses upto 2.5GB physical RAM (RSS).
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adapt - Adaptive mode where ppmd or bzip2 will be used per chunk,
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depending on heuristics. If at least 50% of the input data is
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7-bit text then PPMd will be used otherwise Bzip2.
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adapt2 - Adaptive mode which includes ppmd and lzma. If at least 80% of
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the input data is 7-bit text then PPMd will be used otherwise
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LZMA. It has significantly more memory usage than adapt.
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none - No compression. This is only meaningful with -D and -E so Dedupe
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none - No compression. This is only meaningful with -G or -D. So Dedupe
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can be done for post-processing with an external utility.
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<chunk_size> - This can be in bytes or can use the following suffixes:
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g - Gigabyte, m - Megabyte, k - Kilobyte.
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Larger chunks produce better compression at the cost of memory.
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In case of Global Deduplication (see below) this chunk size is
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just a hint and may get automatically adjusted.
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<compress_level> - Can be a number from 0 meaning minimum and 14 meaning
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maximum compression.
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<target file> - Optional argument specifying the destination compressed
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file. The '.pz' extension is appended. If this is '-' then
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compressed output goes to stdout. If this argument is omitted then
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source filename is used with the extension '.pz' appended.
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Enabled features based on Compression Level
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===========================================
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To decompress a file compressed using above command:
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pcompress -d <compressed file> <target file>
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1 to 3 - No features, just compression and archiving, if needed.
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4 - Global Deduplication with avg block size of 8KB.
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5 - Global Dedup block size 8KB, Adaptive Delta Encoding.
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6 to 8 - Global Dedup block size reduced to 4KB, Adaptive Delta Encoding.
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9 - Global Dedup block size reduced to 2KB, Adaptive Delta Encoding, Dispack.
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10 - Global Dedup block size 2KB, Adaptive Delta Encoding with extra rounds, Dispack,
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LZP Preprocessing
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10 - 14 - Global Dedup block size 2KB, Adaptive Delta Encoding with extra rounds, Dispack,
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LZP Preprocessing, PackJPG filter for Jpegs.
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<compressed file> can be '-' to indicate reading from stdin while write goes
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to <target file>
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Encryption
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==========
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Pcompress supports encryption and authentication in both archive and single-file
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compresion modes. Encryption options are discussed below.
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To operate as a full pipe, read from stdin and write to stdout:
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pcompress -p ...
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NOTE: When using pipe-mode via -p the only way to provide a password is to use '-w'.
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See below.
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Attempt Rabin fingerprinting based deduplication on a per-chunk basis:
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-e <ALGO>
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Encrypt chunks using the given encryption algorithm. The algo parameter
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can be one of AES or SALSA20. Both are used in CTR stream encryption
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mode.
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The password can be prompted from the user or read from a file. Unique
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keys are generated every time pcompress is run even when giving the same
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password. Of course enough info is stored in the compresse file so that
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the key used for the file can be re-created given the correct password.
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Default key length if 256 bits but can be reduced to 128 bits using the
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'-k' option.
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The Scrypt algorithm from Tarsnap is used
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(See: http://www.tarsnap.com/scrypt.html) for generating keys from
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passwords. The CTR mode AES mechanism from Tarsnap is also utilized.
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-w <pathname>
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Provide a file which contains the encryption password. This file must
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be readable and writable since it is zeroed out after the password is
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read.
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-k <key length>
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Specify the key length. Can be 16 for 128 bit keys or 32 for 256 bit
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keys. Default value is 32 for 256 bit keys.
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Advanced usage
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==============
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A variety of advanced options are provided if one wishes fine grained control
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as opposed to automatic settings. If advanced options are used then auto-setting
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of parameters get disabled. The various advanced options are discussed below.
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Attempt Polynomial fingerprinting based deduplication on a per-chunk basis:
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pcompress -D ...
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Perform Delta Encoding in addition to Identical Dedup:
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@ -114,61 +285,39 @@ Usage
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effect greater final compression ratio at the cost of
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higher processing overhead.
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Number of threads can optionally be specified: -t <1 - 256 count>
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Other flags:
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'-L' - Enable LZP pre-compression. This improves compression ratio of all
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-L Enable LZP pre-compression. This improves compression ratio of all
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algorithms with some extra CPU and very low RAM overhead. Using
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delta encoding in conjunction with this may not always be beneficial.
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However Adaptive Delta Encoding is beneficial along with this.
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'-P' - Enable Adaptive Delta Encoding. It can improve compresion ratio further
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-P Enable Adaptive Delta Encoding. It can improve compresion ratio further
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for data containing tables of numerical values especially if those are
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in an arithmetic series. In this implementation basic Delta Encoding is
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combined with Run-Length encoding and Matrix transpose
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NOTE - Both -L and -P can be used together to give maximum benefit on most
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datasets.
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'-S' <cksum>
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- Specify chunk checksum to use:
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CRC64 - Extremely Fast 64-bit CRC from LZMA SDK.
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SHA256 - SHA512/256 version of Intel's optimized (SSE,AVX) SHA2 for x86.
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SHA512 - SHA512 version of Intel's optimized (SSE,AVX) SHA2 for x86.
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KECCAK256 - Official 256-bit NIST SHA3 optimized implementation.
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KECCAK512 - Official 512-bit NIST SHA3 optimized implementation.
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BLAKE256 - Very fast 256-bit BLAKE2, derived from the NIST SHA3
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runner-up BLAKE.
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BLAKE512 - Very fast 256-bit BLAKE2, derived from the NIST SHA3
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runner-up BLAKE.
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'-F' - Perform Fixed Block Deduplication. This is faster than fingerprinting
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-F Perform Fixed Block Deduplication. This is faster than fingerprinting
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based content-aware deduplication in some cases. However this is mostly
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usable for disk dumps especially virtual machine images. This generally
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gives lower dedupe ratio than content-aware dedupe (-D) and does not
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support delta compression.
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'-B' <0..5>
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- Specify an average Dedupe block size. 0 - 2K, 1 - 4K, 2 - 8K ... 5 - 64K.
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-B <0..5>
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Specify an average Dedupe block size. 0 - 2K, 1 - 4K, 2 - 8K ... 5 - 64K.
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Default deduplication block size is 4KB for Global Deduplication and 2KB
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otherwise.
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'-B' 0
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- This uses blocks as small as 2KB for deduplication. This option can be
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-B 0
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This uses blocks as small as 2KB for deduplication. This option can be
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used for datasets of a few GBs to a few hundred TBs in size depending on
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available RAM.
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Caveats:
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In some cases like LZMA with extreme compression levels and with '-L' and
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'-P' preprocessing enabled, this can result in lower compression as compared
|
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to using '-B 1'.
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For fast compression algorithms like LZ4 and Zlib this should always benefit.
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However please test on your sample data with your desired compression
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algorithm to verify the results.
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-M Display memory allocator statistics.
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-C Display compression statistics.
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'-M' - Display memory allocator statistics
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'-C' - Display compression statistics
|
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Global Deduplication:
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'-G' - This flag enables Global Deduplication. This makes pcompress maintain an
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||||
Global Deduplication
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--------------------
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-G This flag enables Global Deduplication. This makes pcompress maintain an
|
||||
in-memory index to lookup cryptographic block hashes for duplicates. Once
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a duplicate is found it is replaced with a reference to the original block.
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This allows detecting and eliminating duplicate blocks across the entire
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|
@ -203,34 +352,6 @@ Usage
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In pipe mode Global Deduplication always uses a segmented similarity based
|
||||
index. It allows efficient network transfer of large data.
|
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|
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Encryption flags:
|
||||
'-e <ALGO>'
|
||||
Encrypt chunks using the given encryption algorithm. The algo parameter
|
||||
can be one of AES or SALSA20. Both are used in CTR stream encryption
|
||||
mode.
|
||||
The password can be prompted from the user or read from a file. Unique
|
||||
keys are generated every time pcompress is run even when giving the same
|
||||
password. Of course enough info is stored in the compresse file so that
|
||||
the key used for the file can be re-created given the correct password.
|
||||
|
||||
Default key length if 256 bits but can be reduced to 128 bits using the
|
||||
'-k' option.
|
||||
|
||||
The Scrypt algorithm from Tarsnap is used
|
||||
(See: http://www.tarsnap.com/scrypt.html) for generating keys from
|
||||
passwords. The CTR mode AES mechanism from Tarsnap is also utilized.
|
||||
|
||||
'-w <pathname>'
|
||||
Provide a file which contains the encryption password. This file must
|
||||
be readable and writable since it is zeroed out after the password is
|
||||
read.
|
||||
|
||||
'-k <key length>'
|
||||
Specify the key length. Can be 16 for 128 bit keys or 32 for 256 bit
|
||||
keys. Default value is 32 for 256 bit keys.
|
||||
|
||||
NOTE: When using pipe-mode via -p the only way to provide a password is to use '-w'.
|
||||
|
||||
Environment Variables
|
||||
=====================
|
||||
|
||||
|
@ -275,72 +396,32 @@ than SHA2.
|
|||
Examples
|
||||
========
|
||||
|
||||
Simple compress "file.tar" using zlib(gzip) algorithm. Default chunk or per-thread
|
||||
Archive contents of directory /usr/include into usr.pz. Default chunk or per-thread
|
||||
segment size is 8MB and default compression level is 6.
|
||||
|
||||
pcompress -a /usr/include usr
|
||||
|
||||
Archive the given listr of files into file.pz and max compresion level and all features
|
||||
enabled. A maximum chunk size of 20MB is used. Also use verbose mode which lists each
|
||||
file as it is processed.
|
||||
|
||||
pcompress -a -v -l14 -s20m file1 file2 file3 file
|
||||
|
||||
Simple compress "file.tar" using zlib(gzip) algorithm. Default chunk or per-thread
|
||||
segment size is 8MB and default compression level is 6. Output file created will be
|
||||
file.tar.pz
|
||||
|
||||
pcompress -c zlib file.tar
|
||||
|
||||
Compress "file.tar" using bzip2 level 6, 64MB chunk size and use 4 threads. In
|
||||
addition perform identity deduplication and delta compression prior to compression.
|
||||
Simple compress "file.tar" using zlib(gzip) algorithm with output file file.compressed.pz
|
||||
|
||||
pcompress -D -E -c bzip2 -l6 -s64m -t4 file.tar
|
||||
pcompress -c zlib file.tar file.compressed
|
||||
|
||||
Compress "file.tar" using zlib and also perform Global Deduplication. Default block
|
||||
size used for deduplication is 4KB. Also redirect the compressed output to stdout and
|
||||
send it to a compressed file at a different path.
|
||||
Compress "file.tar" using Zlib and per-thread chunk or segment size of 10MB and
|
||||
Compression level 9. Compressed output is sent to stdout using '-' which is then
|
||||
redirected to a file.
|
||||
|
||||
pcompress -G -c zlib -l9 -s10m file.tar - > /path/to/compress_file.tar.pz
|
||||
|
||||
Perform the same as above but this time use a deduplication block size of 8KB.
|
||||
|
||||
pcompress -G -c zlib -l9 -B2 -s10m file.tar - > /path/to/compress_file.tar.pz
|
||||
|
||||
Compress "file.tar" using extreme compression mode of LZMA and a chunk size of
|
||||
of 1GB. Allow pcompress to detect the number of CPU cores and use as many threads.
|
||||
|
||||
pcompress -c lzma -l14 -s1g file.tar
|
||||
|
||||
Compress "file.tar" using lz4 at max compression with LZ-Prediction pre-processing
|
||||
and encryption enabled. Chunksize is 100M:
|
||||
|
||||
pcompress -c lz4 -l3 -e -L -s100m file.tar
|
||||
|
||||
Compression Algorithms
|
||||
======================
|
||||
|
||||
LZFX - Ultra Fast, average compression. This algorithm is the fastest overall.
|
||||
Levels: 1 - 5
|
||||
LZ4 - Very Fast, better compression than LZFX.
|
||||
Levels: 1 - 3
|
||||
Zlib - Fast, better compression.
|
||||
Levels: 1 - 9
|
||||
Bzip2 - Slow, much better compression than Zlib.
|
||||
Levels: 1 - 9
|
||||
|
||||
LZMA - Very slow. Extreme compression.
|
||||
Levels: 1 - 14
|
||||
Till level 9 it is standard LZMA parameters. Levels 10 - 12 use
|
||||
more memory and higher match iterations so are slower. Levels
|
||||
13 and 14 use larger dictionaries upto 256MB and really suck up
|
||||
RAM. Use these levels only if you have at the minimum 4GB RAM on
|
||||
your system.
|
||||
|
||||
PPMD - Slow. Extreme compression for Text, average compression for binary.
|
||||
In addition PPMD decompression time is also high for large chunks.
|
||||
This requires lots of RAM similar to LZMA.
|
||||
Levels: 1 - 14.
|
||||
|
||||
Adapt - Synthetic mode with text/binary detection. For pure text data PPMD is
|
||||
used otherwise Bzip2 is selected per chunk.
|
||||
Levels: 1 - 14
|
||||
Adapt2 - Slower synthetic mode. For pure text data PPMD is otherwise LZMA is
|
||||
applied. Can give very good compression ratio when splitting file
|
||||
into multiple chunks.
|
||||
Levels: 1 - 14
|
||||
Since both LZMA and PPMD are used together memory requirements are
|
||||
large especially if you are also using extreme levels above 10. For
|
||||
example with 100MB chunks, Level 14, 2 threads and with or without
|
||||
dedupe, it uses upto 2.5GB physical RAM (RSS).
|
||||
pcompress -c zlib -l9 -s10m file.tar - > /path/to/compress_file.tar.pz
|
||||
|
||||
It is possible for a single chunk to span the entire file if enough RAM is
|
||||
available. However for adaptive modes to be effective for large files, especially
|
||||
|
@ -356,21 +437,21 @@ algorithms can achieve by themselves. These are summarized below:
|
|||
1) Deduplication : Per-Chunk (or per-segment) deduplication based on Rabin
|
||||
fingerprinting.
|
||||
|
||||
2) Delta Compression : A similarity based (minhash) comparison of Rabin blocks. Two
|
||||
blocks at least 60% similar with each other are diffed using
|
||||
bsdiff.
|
||||
2) Delta Compression : A similarity based (minhash) comparison of Rabin blocks.
|
||||
Two blocks at least 60% similar with each other are diffed
|
||||
using bsdiff.
|
||||
|
||||
3) LZP : LZ Prediction is a variant of LZ77 that replaces repeating
|
||||
runs of text with shorter codes.
|
||||
|
||||
4) Adaptive Delta : This is a simple form of Delta Encoding where arithmetic
|
||||
progressions are detected in the data stream and collapsed
|
||||
via Run-Length encoding.
|
||||
progressions are detected in the data stream and
|
||||
collapsed via Run-Length encoding.
|
||||
|
||||
4) Matrix Transpose : This is used automatically in Delta Encoding and Deduplication.
|
||||
This attempts to transpose columnar repeating sequences of
|
||||
bytes into row-wise sequences so that compression algorithms
|
||||
can work better.
|
||||
4) Matrix Transpose : This is used automatically in Delta Encoding and
|
||||
Deduplication. This attempts to transpose columnar
|
||||
repeating sequences of bytes into row-wise sequences so
|
||||
that compression algorithms can work better.
|
||||
|
||||
Memory Usage
|
||||
============
|
||||
|
|
|
@ -230,8 +230,9 @@ adapt_compress(void *src, uint64_t srclen, void *dst,
|
|||
struct adapt_data *adat = (struct adapt_data *)(data);
|
||||
uchar_t *src1 = (uchar_t *)src;
|
||||
int rv = 0, bsc_type = 0;
|
||||
int stype = PC_SUBTYPE(btype);
|
||||
|
||||
if (btype == TYPE_UNKNOWN) {
|
||||
if (btype == TYPE_UNKNOWN || stype == TYPE_ARCHIVE_TAR) {
|
||||
uint64_t i, tot8b, tag1, tag2, tag3;
|
||||
double tagcnt, pct_tag;
|
||||
uchar_t cur_byte, prev_byte;
|
||||
|
@ -267,6 +268,29 @@ adapt_compress(void *src, uint64_t srclen, void *dst,
|
|||
tagcnt > (double)srclen * 0.001)
|
||||
btype |= TYPE_MARKUP;
|
||||
}
|
||||
|
||||
} else if (stype == TYPE_PDF) {
|
||||
uint64_t i, tot8b;
|
||||
uchar_t cur_byte;
|
||||
|
||||
/*
|
||||
* For PDF files we need to check for uncompressed PDFs. Those are compressed
|
||||
* using Libbsc.
|
||||
*/
|
||||
tot8b = 0;
|
||||
for (i = 0; i < srclen; i++) {
|
||||
cur_byte = src1[i];
|
||||
tot8b += (cur_byte & 0x80);
|
||||
}
|
||||
|
||||
tot8b /= 0x80;
|
||||
if (adat->adapt_mode == 2 && tot8b > FORTY_PCT(srclen)) {
|
||||
btype = TYPE_BINARY;
|
||||
} else if (adat->adapt_mode == 1 && tot8b > FIFTY_PCT(srclen)) {
|
||||
btype = TYPE_BINARY;
|
||||
} else {
|
||||
btype = TYPE_TEXT|TYPE_MARKUP;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
|
@ -46,6 +46,7 @@ struct filter_info {
|
|||
struct archive_entry *entry;
|
||||
int fd;
|
||||
int compressing, block_size;
|
||||
int *type_ptr;
|
||||
};
|
||||
|
||||
struct filter_flags {
|
||||
|
|
|
@ -842,7 +842,7 @@ setup_extractor(pc_ctx_t *pctx)
|
|||
}
|
||||
|
||||
static ssize_t
|
||||
process_by_filter(int fd, int typ, struct archive *target_arc,
|
||||
process_by_filter(int fd, int *typ, struct archive *target_arc,
|
||||
struct archive *source_arc, struct archive_entry *entry, int cmp)
|
||||
{
|
||||
struct filter_info fi;
|
||||
|
@ -854,10 +854,11 @@ process_by_filter(int fd, int typ, struct archive *target_arc,
|
|||
fi.fd = fd;
|
||||
fi.compressing = cmp;
|
||||
fi.block_size = AW_BLOCK_SIZE;
|
||||
wrtn = (*(typetab[(typ >> 3)].filter_func))(&fi, typetab[(typ >> 3)].filter_private);
|
||||
fi.type_ptr = typ;
|
||||
wrtn = (*(typetab[(*typ >> 3)].filter_func))(&fi, typetab[(*typ >> 3)].filter_private);
|
||||
if (wrtn == FILTER_RETURN_ERROR) {
|
||||
log_msg(LOG_ERR, 0, "Error invoking filter module: %s",
|
||||
typetab[(typ >> 3)].filter_name);
|
||||
typetab[(*typ >> 3)].filter_name);
|
||||
}
|
||||
return (wrtn);
|
||||
}
|
||||
|
@ -890,7 +891,8 @@ copy_file_data(pc_ctx_t *pctx, struct archive *arc, struct archive_entry *entry,
|
|||
if (typetab[(typ >> 3)].filter_func != NULL) {
|
||||
int64_t rv;
|
||||
|
||||
rv = process_by_filter(fd, typ, arc, NULL, entry, 1);
|
||||
pctx->ctype = typ;
|
||||
rv = process_by_filter(fd, &(pctx->ctype), arc, NULL, entry, 1);
|
||||
if (rv == FILTER_RETURN_ERROR) {
|
||||
close(fd);
|
||||
return (-1);
|
||||
|
@ -934,7 +936,7 @@ do_map:
|
|||
int64_t rv;
|
||||
munmap(mapbuf, len);
|
||||
|
||||
rv = process_by_filter(fd, typ, arc, NULL, entry, 1);
|
||||
rv = process_by_filter(fd, &(pctx->ctype), arc, NULL, entry, 1);
|
||||
if (rv == FILTER_RETURN_ERROR) {
|
||||
return (-1);
|
||||
} else if (rv == FILTER_RETURN_SKIP) {
|
||||
|
@ -1149,7 +1151,7 @@ copy_data_out(struct archive *ar, struct archive *aw, struct archive_entry *entr
|
|||
if (typetab[(typ >> 3)].filter_func != NULL) {
|
||||
int64_t rv;
|
||||
|
||||
rv = process_by_filter(-1, typ, aw, ar, entry, 0);
|
||||
rv = process_by_filter(-1, &typ, aw, ar, entry, 0);
|
||||
if (rv == FILTER_RETURN_ERROR) {
|
||||
archive_set_error(ar, archive_errno(aw),
|
||||
"%s", archive_error_string(aw));
|
||||
|
@ -1231,6 +1233,7 @@ extractor_thread_func(void *dat) {
|
|||
* Extract all security attributes if we are root.
|
||||
*/
|
||||
if (pctx->force_archive_perms || geteuid() == 0) {
|
||||
if (geteuid() == 0)
|
||||
flags |= ARCHIVE_EXTRACT_OWNER;
|
||||
flags |= ARCHIVE_EXTRACT_PERM;
|
||||
flags |= ARCHIVE_EXTRACT_ACL;
|
||||
|
@ -1475,17 +1478,21 @@ out:
|
|||
* Detect a few file types from looking at magic signatures.
|
||||
* NOTE: Jpeg files must be detected via '.jpg' or '.jpeg' (case-insensitive)
|
||||
* extensions. Do not add Jpeg header detection here. it will break
|
||||
* context based PackJPG processing. Jpeg files not have proper
|
||||
* context based PackJPG processing. Jpeg files not having proper
|
||||
* extension must not be processed via PackJPG.
|
||||
*/
|
||||
static int
|
||||
detect_type_by_data(uchar_t *buf, size_t len)
|
||||
{
|
||||
// At least a few bytes.
|
||||
if (len < 16) return (TYPE_UNKNOWN);
|
||||
if (len < 512) return (TYPE_UNKNOWN);
|
||||
|
||||
if (memcmp(buf, "!<arch>\n", 8) == 0)
|
||||
return (TYPE_BINARY|TYPE_ARCHIVE_AR);
|
||||
if (memcmp(&buf[257], "ustar\0", 6) == 0 || memcmp(&buf[257], "ustar\040\040\0", 8) == 0)
|
||||
return (TYPE_BINARY|TYPE_ARCHIVE_TAR);
|
||||
if (memcmp(buf, "%PDF-", 5) == 0)
|
||||
return (TYPE_BINARY|TYPE_PDF);
|
||||
if (U32_P(buf) == ELFINT) { // Regular ELF, check for 32/64-bit, core dump
|
||||
if (*(buf + 16) != 4) {
|
||||
if (*(buf + 4) == 2) {
|
||||
|
|
11
pcompress.c
11
pcompress.c
|
@ -2832,7 +2832,7 @@ init_pc_context(pc_ctx_t *pctx, int argc, char *argv[])
|
|||
ff.enable_packjpg = 0;
|
||||
|
||||
pthread_mutex_lock(&opt_parse);
|
||||
while ((opt = getopt(argc, argv, "dc:s:l:pt:MCDGEe:w:LPS:B:Fk:avnmK")) != -1) {
|
||||
while ((opt = getopt(argc, argv, "dc:s:l:pt:MCDGEe:w:LPS:B:Fk:avmK")) != -1) {
|
||||
int ovr;
|
||||
int64_t chunksize;
|
||||
|
||||
|
@ -2982,10 +2982,6 @@ init_pc_context(pc_ctx_t *pctx, int argc, char *argv[])
|
|||
pctx->verbose = 1;
|
||||
break;
|
||||
|
||||
case 'n':
|
||||
pctx->enable_archive_sort = -1;
|
||||
break;
|
||||
|
||||
case 'm':
|
||||
pctx->force_archive_perms = 1;
|
||||
break;
|
||||
|
@ -3023,6 +3019,11 @@ init_pc_context(pc_ctx_t *pctx, int argc, char *argv[])
|
|||
return (1);
|
||||
}
|
||||
|
||||
if (pctx->archive_mode && pctx->pipe_mode) {
|
||||
log_msg(LOG_ERR, 0, "Full pipeline mode is meaningless with archiver.");
|
||||
return (1);
|
||||
}
|
||||
|
||||
/*
|
||||
* Default compression algorithm during archiving is Adaptive2.
|
||||
*/
|
||||
|
|
|
@ -236,7 +236,7 @@ typedef struct pc_ctx {
|
|||
uchar_t *arc_buf;
|
||||
uint64_t arc_buf_size, arc_buf_pos;
|
||||
int arc_closed, arc_writing;
|
||||
uchar_t btype, ctype;
|
||||
int btype, ctype;
|
||||
int min_chunk;
|
||||
int enable_packjpg;
|
||||
|
||||
|
|
|
@ -246,7 +246,7 @@ typedef enum {
|
|||
/*
|
||||
* Sub-types.
|
||||
*/
|
||||
#define NUM_SUB_TYPES 26
|
||||
#define NUM_SUB_TYPES 28
|
||||
TYPE_EXE32 = 8,
|
||||
TYPE_JPEG = 16,
|
||||
TYPE_MARKUP = 24,
|
||||
|
@ -272,7 +272,9 @@ typedef enum {
|
|||
TYPE_AUDIO_COMPRESSED = 184,
|
||||
TYPE_EXE64 = 192,
|
||||
TYPE_BMP = 200,
|
||||
TYPE_TIFF = 208
|
||||
TYPE_TIFF = 208,
|
||||
TYPE_PDF = 216,
|
||||
TYPE_ARCHIVE_TAR = 224
|
||||
} data_type_t;
|
||||
|
||||
/*
|
||||
|
|
Loading…
Reference in a new issue