cached(1M)                                                          cached(1M)



NAME
     cached - monitor single bit secondary cache errors.

SYNOPSIS
     cached [-s size] [-S delay] [-fC] [-p priority]

DESCRIPTION
     cached monitors the number of single bit errors in the secondary cache of
     each cpu. It reports the number of single bit errors encountered on any
     cpu each time it runs.

     The -s size parameter determines the size of the cpu secondary cache in
     bytes.  If no value is specified, the default value of 4194304 (4 MB) is
     used.

     The -S delay parameter indicates the amount of time to wait each time
     between examining the secondary caches. This delay is in seconds and the
     default is 3600 seconds (one hour).  The -C option must be used for this
     option to mean anything useful.

     The -p priority parameter indicates the priority cached will be run at.
     The value can be in the range -20 to 20 with -20 being the highest
     priority and 20 being the lowest.  The priority defaults to 10.

     The -f parameter indicates that cached should run on all enabled cpus.
     Normally cached does not run on restricted cpus.

     The -C parameter indicates that cached should run continuously, sleeping
     and running the check of secondary caches forever.  If this option is not
     specified, the program runs once and then exits.


OVERVIEW
     cached uses the R10000 performance registers at the user level to monitor
     the number of single bit cache errors. Single bit errors are
     automatically corrected by the hardware. If the secondary cache has
     numerous single bit errors, there is a possibility that these could turn
     into multi-bit errors which are fatal for the system. Monitoring the
     number of single bit errors provides a means of warning the user early
     enough so that the cpu module containing the cache may be replaced.

     cached runs at a very low priority by default so as not to interfere with
     the normal usage of the machine.


NOTES
     cached is run as a cron job and can be turned off or controlled using the
     diagsetup script.

     To avoid disruptions to real-time usage, cached normally does not run on
     isolated or restricted cpus. This can be overriden by using the -f flag.




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cached(1M)                                                          cached(1M)



FILES
     /usr/diags                 the diag user's home directory
     /usr/diags/bin/cached      location of cached executable
     /usr/diags/bin/diagsetup   script to control the periodic running of
                                testfpu and cached

FILES
SEE ALSO
     testfpu(1M), diagsetup(1M)



RESTRICTIONS
     This command works only on MIPS R10000 systems.









































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