Contributed by Jon Haslam
Solaris 10 delivered a revolutionary new subsystem called the Solaris Dynamic Tracing Framework (or DTrace for short). DTrace is an observability technology that allows us, for the first time, to answer virtually every question we ever wanted to ask about the behavior of our systems and applications.
Before Solaris 10, the Solaris observational toolset was already quite rich; many examples in this book use tools such as
iostat(1), and others. However, as rich as each individual tool is, it still provides only limited and fixed insight into one specific area of a system. Not only that, but each of the tools is disjoint in its operation. ...