NAME

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

SYNOPSIS

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

DESCRIPTION

       cache-clean  is  a tool for administrators of ARC server installations to safely remove A-
       REX cache data and to provide an overview of the contents of the 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 space used by the cache on the file system is more than that given by
       -M, in the order of least recently accessed, until the space used by the cache is equal to
       what  is  specified  by -m.  If -E is used, then all files accessed less recently than the
       given time are deleted.  -E can be used in combination with -m and -M but  deleting  files
       using  -E is carried out first. If after this the cache used space is still more than that
       given by -M then cleaning according to those options is performed.

       If the cache is on a file system shared with other data then -S  should  be  specified  so
       that  the  space used by the cache is calculated. Otherwise all the used space on the file
       system is assumed to be for the cache. Using -S is slower so should only be used when  the
       cache is shared.

       By  default  the "df" command is used to determine total and (if -S is not specified) used
       space. If this command is not supported on the cache file system then -f can  be  used  to
       specify an alternate command. The output of this command must be "total_bytes used_bytes",
       and so the command would  normally  be  a  small  script  around  the  file  system  space
       information tool. The cache directory is passed as the last argument to this command.

       Cache 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.

       -S - Calculate the size of the cache instead of taking used space on the file system. This
       should only be used when the cache file system is shared with other data.

       -M - the maximum used space (as % of the file system) at which to start cleaning

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

       -E - files accessed less recently than the given time  period  will  be  deleted.  Example
       values  of  this  option  are  1800, 90s, 24h, 30d. The default when no suffix is given is
       seconds.

       -f - alternative command to "df" for obtaining the file system total and used  space.  The
       output  of this command must be "total_bytes used_bytes". The cache directory is passed as
       the last argument to this command.

       -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 -E30d -D VERBOSE -c /etc/arc.conf

       Cache directories are taken from the configuration file /etc/arc.conf and all cache  files
       accessed  more  than  30  days ago are deleted. Then if the used space in a cache is above
       30%, data is deleted until the used space reaches 20%. Verbose debug output is enabled  so
       information is output on each file that is deleted.

COPYRIGHT

       APACHE LICENSE Version 2.0

AUTHOR

       ARC  software  is  developed  by  the  NorduGrid Collaboration (http://www.nordugrid.org),
       please consult the AUTHORS file distributed with  ARC.  Please  report  bugs  and  feature
       requests to http://bugzilla.nordugrid.org