js_stat.d - JavaScript operation stats using DTrace. js_stat.d [interval [count]] This traces activity from all browsers on the system that are running with JavaScript provider support. The numbers are counts for the interval specified. The default interval is 1 second. Filename and function names are printed if available. Any Evolving - uses the DTrace JavaScript provider, which may change as additional features are introduced. Check JavaScript/Readme to see what version these scripts are based on.

Default output, # js_stat.d

EXEC/s JavaScript programs executed per second

FUNCS/s Functions called, per second

OBJNEW/s Objects created, per second

OBJFRE/s Objects freed (finalize), per second

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. js_stat.d will run until Ctrl-C is hit. Brendan Gregg [CA, USA] dtrace(1M)