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)