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cache-clean

NAME

cache-clean - Administration tool for the A-REX cache.

SYNOPSIS

cache-clean -h | -s | -m NN -M NN [-D debug_level]
  [ -c <arex_config_file> | <dir1> [<dir2> [...]] ]

DESCRIPTION

cache-clean is a tool for administrators of ARC server installations to safely remove data and provide an overview of the contents of the A-REX cache. It is used by the A-REX to automatically manage cache contents.

There are two modes of operation - printing statistics and deleting files. If -s is used, then statistics are printed on each cache. If -m and -M are used then files in each cache are deleted if the free space on the file system is less than that given by -m, until the free space is equal to what is specified by -M. Caches directories are given by dir1, dir2.. or taken from the config file specified by -c or the ARC_CONFIG environment variable.

-h - print short help

-s - print cache statistics, without deleting anything. The output displays for each cache the number of deletable (and locked) files, the total size of these files, the percentage usage of the file system in which the cache is stored, and a histogram of access times of the files in the cache.

-m - the minimum free space (as % of the file system) at which to start cleaning

-M - the minimum free space (as % of the file system) at which to stop cleaning

-D - debug level. Possible values are FATAL, ERROR, WARNING, INFO, VERBOSE or DEBUG. Default level is INFO.

-c - path to an A-REX config file, xml or ini format

This tool is run periodically by the A-REX to keep the size of each cache within the limits specified in the configuration file. Therefore cleaning should not be performed manually, unless the cache size needs to be reduced temporarily. For performance reasons it may however be desirable to run cache-clean independently on the machine hosting the cache file system, if this is different from the A-REX host. The most useful function for administrators is to give an overview of the contents of the cache, using the -s option.

Within each cache directory specified in the configuration file, there is a subdirectory for data (data/) and one for per-job hard links (joblinks/). See the A-REX Administration Guide for more details. cache-clean should only operate on the data subdirectory, therefore when giving dir arguments they should be the top level cache directory. cache-clean will then automatically only look at files within the data directory.

EXAMPLE

cache-clean -m20 -M30 -D VERBOSE -c /etc/arc.conf

Cache directories are taken from the configuration file /etc/arc.conf and if the free space in a cache is below 20%, data is deleted until the free space reaches 30%. Verbose debug output is enabled so information is output on each file that is deleted.

COPYRIGHT

APACHE LICENSE Version 2.0

AUTHOR

David Cameron <cameron@ndgf.org>