Top 10 DTrace scripts for Mac OS X
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. I’m familiar with the latter as I wrote the originals for theDTraceToolkit, which Apple then customized and enhanced for Mac OS X where they are shipped by default (great!). I use them regularly to answer this question:
why is my MacBook slow?
I work in an office where everyone has MacBook Pros, and “why is my MacBook slow?” is a common question. Applications can become slow or unresponsive while waiting for CPU work, memory requests or disk I/O to complete.
Standard performance analysis tools like Activity Monitor and top(1) (and any third-party tools based on the same foundation) can’t tell you some key information about activity on your system, such as how much CPU consumption is caused by short-lived processes, or which processes are causing disk I/O. DTrace, however, can see (just about) everything.
Source: Brendan’s blog
DTrace is a wonderful CLI utility for OS X that lets you get your geek on. There’s no way I’m going to try and improve on the blog post on Brendan’s Blog.
This probably geekier than most OS X users are comfortable, but if you’re familiar with Bash, you shouldn’t have too many troubles with it.