PMLOGCOMPRESS(1)            General Commands Manual           PMLOGCOMPRESS(1)

NAME
       pmlogcompress - compress and decompress PCP archive files

SYNOPSIS
       pmlogcompress [-dNVz?] [-A arg] [-c proglist] [-f prog] [-l limit] [-o
       type] [-t dir] [-Z min] archive]...

DESCRIPTION
       pmlogcompress supports the compression and decompression of the files
       that make up a Performance Co-Pilot (PCP) archive; refer to
       LOGARCHIVE(5) for an explanation of the various files that are
       components of a PCP archive.

       The archive arguments may be either the name of a single file in a PCP
       archive or the basename of a PCP archive, as in the style generated by
       pmlogbasename(1).  In the former case, pmlogcompress will compress or
       decompress just that file, but in the latter case pmlogcompress will
       attempt to compress or decompress all the files that are part of the
       associated PCP archive.

       In keeping with other compression tools, the default mode for
       pmlogcompress is to compress, i.e. the -z option, to decompress the -d
       option is required.

OPTIONS
       The available command line options are:

       -A arg, --arg=arg
            arg is used as an argument to the compression program; most likely
            useful with the -f option so that the choice of compression
            program is deterministic.

            The processing of arg is not sophisticated, so embedded shell
            variables, escape characters, shell ``glob'' characters and white
            space should be avoided.

            Multiple -A options are allowed and all the arg arguments will be
            used.

       -c proglist, --command=proglist
            Depending on other command line options, and the availability of
            installed compression programs, the choice if program when
            compressing may vary.  The -c option allows a list of compression
            programs to be provided, either with multiple -c options and/or by
            separating program names in proglist by a colon, in the style of
            the shell's $PATH notation.

            The default value for proglist is zstd:xz:bzip2:gzip.

       -f prog, --use=prog
            If only one program is to be considered for compression then this
            may be specified using the -f option.  The effect is the same as
            if only one -c option was used, and proglist contained exactly one
            program name, namely prog.

       -d, --decompress
            Choose decompression mode.  The suffix of each file associated
            with archive determines the decompression tool to be used.

       -l limit, --lower-limit=limit
            When compressing, do not consider files smaller than limit
            (bytes).

       -N, --show-me
            Do nothing, but show what commands would have been executed.

       -o type, --optimize=type
            When compressing the -o option will try to pick the compression
            program from proglist (see the -c option above) that does the
            ``best'' job, where type may be size to choose the compression
            program that produces the smallest output file, or cpu to choose
            the compression program that uses the least CPU time.

            If archive is an archive basename then the largest of the files
            that are part of the associated PCP archive is selected for the
            test, else archive will be used for the test.

            Use of this option means each of the selected archive files will
            be compressed multiple times, so it is likely that -o would be
            used in experiments with -N (and possibly -V) to determine the
            best compression tool for the local environment and PCP archives.

       -t dir, --dir=dir
            When decompressing any compressed files will (by default) be
            replaced by their decompressed equivalent.  The -t option changes
            this behavior to create a duplicate, uncompressed archive in the
            dir directory.

            If archive is a single file, then only that file is decompressed
            into dir, but if archive is an archive basename then all of the
            files of archive will be copied, and possibly decompressed, into
            dir.

            dir must exist before pmlogcompress is run.

       -V, --verbose
            Increase verbosity.

       -z, --compress
            Choose compression mode (the default).

       -Z min, --min-zstd-size=min
            xz(1) produces smaller compressed files for small input files, but
            at some point the input file becomes large enough that zstd(1)
            produces smaller compressed files and zstd is typically much
            faster.

            When both xz and xstd are in consideration (see the -c option
            above), then the -Z option allows the user to tune where the xz to
            zstd cut-over happens; input files smaller than min (in bytes)
            will be compressed with xz else zstd will be used.

            The default value for min is 52428800 (50MiB).

       -?, --help
            Display usage message and exit.

SEE ALSO
       PCPIntro(1), bzip2(1), gzip(1), pmlogbasename(1), pmlogger(1),
       pmlogger_check(1), pmlogger_daily(1), xz(1), zstd(1) and LOGARCHIVE(5).


TODO
       back reference to pmlogger_daily and friends where all the compression
       is done at the moment


Performance Co-Pilot                  PCP                     PMLOGCOMPRESS(1)