cache-clean - Administration tool for the A-REX cache.
cache-clean [-h] [-s] [-S] [-m NN -M NN] [-E N] [-D debug_level]
[-f space_command] [ -c <arex_config_file> | <dir1> [<dir2>
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
is used, then statistics are printed on each cache. If -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,
order of least recently accessed, until the space used by the cache is equal
to what is specified by -m.
is used, then all files
accessed less recently than the given time are deleted. -E
can be used
in combination with -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
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
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.
- print short help
- 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.
- 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.
- the maximum used space (as % of the file system) at which to start
- the minimum used space (as % of the file system) at which to stop
- 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.
- 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
- debug level. Possible values are FATAL, ERROR, WARNING, INFO,
VERBOSE or DEBUG. Default level is INFO.
- 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
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
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.
cache-clean -m20 -M30 -E30d -D VERBOSE -c /etc/arc.conf
Cache directories are taken from the configuration file /etc/arc.conf
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.
APACHE LICENSE Version 2.0
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