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fddist(1m)                                      USER COMMANDS                                     fddist(1m)



NAME
       fddist - file descriptor usage distributions. Uses DTrace.

SYNOPSIS
       fddist [-r|-w]

DESCRIPTION
       This  prints distributions for read and write events by file descriptor, by process. This can be used
       to determine which file descriptor a process is doing the most I/O with.

       Since this uses DTrace, only the root user or users with the dtrace_kernel  privilege  can  run  this
       command.

OPTIONS
       -r     reads only

       -w     writes only


EXAMPLES
       Sample both read and write activity,
              # fddist

       Sample reads only,
              # fddist -r


FIELDS
       EXEC   process name

       PID    process ID

       value  file descriptor

       count  number of events


BASED ON
       /usr/demo/dtrace/lquantize.d


DOCUMENTATION
       DTrace Guide "Aggregations" chapter (docs.sun.com)

       See  the DTraceToolkit for further documentation under the Docs directory. The DTraceToolkit docs may
       include full worked examples with verbose descriptions explaining the output.

EXIT
       fddist will sample until Ctrl-C is hit.

SEE ALSO
       dtrace(1M)




version 0.70                                    Jun 08, 2005                                      fddist(1m)