The size of the window in terms of characters is also small (80 columns by 24 rows), presumably to pay homage to original Unix terminals of that size. Mac OS X is Unix under the hood: the Darwin kernel).
Since version 10.5 “Leopard”, Mac OS X has had DTrace, a tool used for performance analysis and troubleshooting.
It provides data for Apple’s Instruments tool, as well as a collection of command line tools that are implemented as DTrace scripts.
The output columns show: UID = user ID, PID = process ID (unique identifier for the process), D = direction (R = read, W = write), BLOCK = location on disk, SIZE = I/O size in bytes, COMM = process name, PATHNAME = trailing portion of file pathname.
In that output I caught Google Chrome reading from a cache file (“data_2″), and writing to cookie files (“Cookies-journal” and “Cookies”).
If firefox stayed that high you could look for the responsible tab and close it down, or restart Firefox. DTrace requires admin privileges, so to use it you’ll usually need to type in a password to authenticate, provided you have administrator access (if you aren’t sure you do, click here to see how to check).
You can run DTrace by prefixing your DTrace commands with “sudo”, which will prompt for the password the first time around (but not for some time after that)./Default/Cookies-journal 503 54079 W 134993856 4096 Google Chrome ??/Default/Cookies 503 54079 W 134994056 4096 Google Chrome ??For example, here’s my screen as I write this blog post (in a terminal-based text editor).While DTrace can see everything, there are some things already covered by easy-to-use (and easy-to-type) tools, like top(1)./Local Store/td_26_503 65002 W 385001320 4096 Tweet Deck ??