12. Kernel
The operating system kernel is the software at the heart of a system, managing system resources and user processes. It has historically been difficult to observe as it executes in a protected context, beyond the reach of process debuggers. DTrace provides custom visibility into kernel operations, allowing you to answer questions such as the following.
• Where is the kernel spending time consuming CPU cycles?
• What kernel memory allocations are occurring, and for which segments?
• When are functions executing? And with what arguments?
• Why are functions being executed? What is their stack backtrace?
• How long does it take to execute kernel functions? On-cpu/off-cpu?
As an example, the following one-liner traces all kernel function ...
Get The Official Ubuntu Server Book, 3rd Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
