rb_flowinfo.d - snoop Ruby function (method) flow with info using DTrace. rb_flowinfo.d This traces activity from all Ruby programs on the system that are running with Ruby provider support. Filename and method names are printed if available. Any Evolving - uses the DTrace Ruby provider, which may change as additional features are introduced. Check Ruby/Readme to see what version these scripts are based on.

Default output, # rb_flowinfo.d

C CPU-id

PID Process ID

DELTA(us) Elapsed time from previous line to this line

FILE Filename of the Ruby program

LINE Line number of filename

TYPE Type of call (method)

NAME Ruby class and method name

-> method entry

<- method return

Watch the first column carefully, it prints the CPU-id. If it changes, then it is very likely that the output has been shuffled.

See the DTraceToolkit for further documentation under the Examples, Notes and Docs directories. The example files may be especially useful as they aim to demonstrate how to interpret the output. rb_flowinfo.d will run until Ctrl-C is hit. Brendan Gregg [CA, USA] dtrace(1M)