NAME

dappprof - profile user and lib function usage. Uses DTrace.

SYNOPSIS

dappprof [-acehoTU] [-u lib] { -p PID | command }

DESCRIPTION

dappprof prints details on user and library call times for processes as a summary style aggragation. By default the user fuctions are traced, options can be used to trace library activity. Output can include function counts, elapsed times and on cpu times.

The elapsed times are interesting, to help identify functions that take some time to complete (during which the process may have slept). CPU time helps us identify syscalls that are consuming CPU cycles to run.

Since this uses DTrace, only users with root privileges can run this command.

OPTIONS

-a: print all data
-c: print function counts
-e: print elapsed times, ns
-o: print CPU times, ns
-T: print totals
-p PID: examine this PID
-u lib: trace this library instead
-U: trace all library and user functions

EXAMPLES

run and examine the "df -h" command,: # dappprof df -h
print elapsed times, on-cpu times and counts for "df -h",: # dappprof -ceo df -h
print elapsed times for PID 1871,: # dappprof -p 1871
print all data for PID 1871,: # dappprof -ap 1871

FIELDS

CALL: Function call name
ELAPSED: Total elapsed time, nanoseconds
CPU: Total on-cpu time, nanoseconds
COUNT: Number of occurrences

DOCUMENTATION

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

dappprof will sample until Ctrl-C is hit.

AUTHOR

Brendan Gregg [Sydney, Australia]