dtruss

dtruss(1m)                        USER COMMANDS                       dtruss(1m)



NAME
       dtruss - process syscall details. Uses DTrace.

SYNOPSIS
       dtruss [-acdeflhoLs] [-t syscall] { -p PID | -n name | command }

DESCRIPTION
       dtruss prints details on process system calls. It is like a DTrace
       version of truss, and has been designed to be less intrusive than truss.

       Of particular interest is the elapsed times and on cpu times, which can
       identify both system calls that are slow to complete, and those which are
       consuming CPU cycles.

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

OPTIONS
       -a     print all details

       -b bufsize
              dynamic variable buffer size. Increase this if you notice dynamic
              variable drop errors. The default is "4m" for 4 megabytes per CPU.

       -c     print system call counts

       -d     print relative timestamps, us

       -e     print elapsed times, us

       -f     follow children as they are forked

       -l     force printing of pid/lwpid per line

       -L     don't print pid/lwpid per line

       -n name
              examine processes with this name

       -W name
              wait for a process matching this name

       -o     print on-cpu times, us

       -s     print stack backtraces

       -p PID examine this PID

       -t syscall
              examine this syscall only

EXAMPLES
       run and examine the "df -h" command
              # dtruss df -h

       examine PID 1871
              # dtruss -p 1871

       examine all processes called "tar"
              # dtruss -n tar

       run test.sh and follow children
              # dtruss -f test.sh

       run the "date" command and print elapsed and on cpu times,
              # dtruss -eo date

FIELDS
       PID/LWPID
              Process ID / Lightweight Process ID

       RELATIVE
              relative timestamps to the start of the thread, us (microseconds)

       ELAPSD elapsed time for this system call, us

       CPU    on-cpu time for this system call, us

       SYSCALL(args)
              system call name, with arguments (some may be evaluated)

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
       dtruss will run forever until Ctrl-C is hit, or if a command was executed
       dtruss will finish when the command ends.

AUTHOR
       Brendan Gregg [Sydney, Australia]

SEE ALSO
       procsystime(1M), dtrace(1M), truss(1)




version 0.80                      June 17, 2005                       dtruss(1m)