ae3dededed
Previous method would produce too many time() invocations, becoming a significant fraction of workload measured. The new strategy is to use time() only once per batch, and dynamically resize batch size so that each round lasts approximately 1 second. This only matters for small inputs. Measurement for large files (such as silesia.tar) are much less impacted (though decoding speed is so fast that even medium-size files will notice an improvement). |
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| .. | ||
| .gitignore | ||
| bench.c | ||
| bench.h | ||
| COPYING | ||
| datagen.c | ||
| datagen.h | ||
| lz4.1 | ||
| lz4.1.md | ||
| lz4cli.c | ||
| lz4io.c | ||
| lz4io.h | ||
| Makefile | ||
| platform.h | ||
| README.md | ||
| util.h | ||
Command Line Interface for LZ4 library
Command Line Interface (CLI) can be created using the make command without any additional parameters.
There are also multiple targets that create different variations of CLI:
lz4: default CLI, with a command line syntax close to gziplz4c: Same aslz4with additional support legacy lz4 commands (incompatible with gzip)lz4c32: Same aslz4c, but forced to compile in 32-bits mode
Aggregation of parameters
CLI supports aggregation of parameters i.e. -b1, -e18, and -i1 can be joined into -b1e18i1.
Benchmark in Command Line Interface
CLI includes in-memory compression benchmark module for lz4. The benchmark is conducted using a given filename. The file is read into memory. It makes benchmark more precise as it eliminates I/O overhead.
The benchmark measures ratio, compressed size, compression and decompression speed.
One can select compression levels starting from -b and ending with -e.
The -i parameter selects a number of seconds used for each of tested levels.
Usage of Command Line Interface
The full list of commands can be obtained with -h or -H parameter:
Usage :
lz4 [arg] [input] [output]
input : a filename
with no FILE, or when FILE is - or stdin, read standard input
Arguments :
-1 : Fast compression (default)
-9 : High compression
-d : decompression (default for .lz4 extension)
-z : force compression
-f : overwrite output without prompting
--rm : remove source file(s) after successful de/compression
-h/-H : display help/long help and exit
Advanced arguments :
-V : display Version number and exit
-v : verbose mode
-q : suppress warnings; specify twice to suppress errors too
-c : force write to standard output, even if it is the console
-t : test compressed file integrity
-m : multiple input files (implies automatic output filenames)
-r : operate recursively on directories (sets also -m)
-l : compress using Legacy format (Linux kernel compression)
-B# : Block size [4-7] (default : 7)
-BD : Block dependency (improve compression ratio)
--no-frame-crc : disable stream checksum (default:enabled)
--content-size : compressed frame includes original size (default:not present)
--[no-]sparse : sparse mode (default:enabled on file, disabled on stdout)
Benchmark arguments :
-b# : benchmark file(s), using # compression level (default : 1)
-e# : test all compression levels from -bX to # (default : 1)
-i# : minimum evaluation time in seconds (default : 3s)
-B# : cut file into independent blocks of size # bytes [32+]
or predefined block size [4-7] (default: 7)
License
All files in this directory are licensed under GPL-v2. See COPYING for details. The text of the license is also included at the top of each source file.