zstd - Online in the Cloud

PROGRAM:

NAME

zstd, unzstd, zstdcat - Compress or decompress .zst files

SYNOPSIS

zstd [OPTIONS] [-|INPUT-FILE] [-o <OUTPUT-FILE>]

unzstd is equivalent to zstd -d
zstdcat is equivalent to zstd -dc

DESCRIPTION

zstd is a fast lossless compression algorithm. It is based on the LZ77 family, with
further FSE & huff0 entropy stages. zstd offers configurable compression speed, with fast
modes at > 200 MB/s per core. It also features a very fast decoder, with speed > 500 MB/s
per core.

zstd command line is generally similar to gzip, but features the following differences :
- Original files are preserved
- By default, when compressing a single file, zstd displays progress notifications and
result summary.
Use -q to turn them off

zstd supports the following options :

OPTIONS

-#
# compression level [1-21] (default:1)

-d, --decompress
decompression

-D file
use `file` as Dictionary to compress or decompress FILE(s)

-o file
save result into `file` (only possible with a single input FILE)

-f, --force
overwrite output without prompting

-h/-H, --help
display help/long help and exit

-V, --version
display Version number and exit

-v, --verbose
verbose mode

-q, --quiet
suppress warnings and notifications; specify twice to suppress errors too

-c, --stdout
force write to standard output, even if it is the console

DICTIONARY

zstd offers dictionary compression, useful for very small files and messages. It's
possible to train zstd with some samples, the result of which is saved into a file called
`dictionary`. Then during compression and decompression, make reference to the same
dictionary. It will improve compression ratio of small files. Typical gains range from
~10% (at 64KB) to x5 better (at <1KB).

--train FILEs
use FILEs as training set to create a dictionary.
The training set should contain a lot of small files (> 100).
and weight typically 100x the target dictionary size
(for example, 10 MB for a 100 KB dictionary)

-o file
dictionary saved into `file` (default: dictionary)

--maxdict #
limit dictionary to specified size (default : 112640)

-s#
dictionary selectivity level (default: 9)
the smaller the value, the denser the dictionary, improving its efficiency but
reducing its possible maximum size.

BENCHMARK

-b#
benchmark file(s) using compression level #

-i#
iteration loops [1-9](default : 3), benchmark mode only

-B#
cut file into independent blocks of size # (default: no block)

-r#
test all compression levels from 1 to # (default: disabled)

Use zstd online using onworks.net services