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 users with root privileges 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.