重要的能解决的问题是这些:
perf_events is an event-oriented observability tool, which can help you solve advanced performance and troubleshooting functions. Questions that can be answered include:
- Why is the kernel on-CPU so much? What code-paths?
 - Which code-paths are causing CPU level 2 cache misses?
 - Are the CPUs stalled on memory I/O?
 - Which code-paths are allocating memory, and how much?
 - What is triggering TCP retransmits?
 - Is a certain kernel function being called, and how often?
 - What reasons are threads leaving the CPU?
 

原文地址:Linux perf Examples
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