Visible to Intel only — GUID: iga1401400276043
Ixiasoft
Visible to Intel only — GUID: iga1401400276043
Ixiasoft
37.1. Core Overview
The main benefit of using the performance counter core is the accuracy of the profiling results. Alternatives include the following approaches:
- GNU profiler, gprof—gprof provides broad low-precision timing information about the entire software system. It uses a substantial amount of RAM, and degrades the real-time performance. For many embedded applications, gprof distorts real-time behavior too much to be useful.
- Interval timer peripheral—The interval timer is less intrusive than gprof. It can provide good results for narrowly targeted sections of code.
The performance counter core is unobtrusive, requiring only a single instruction to start and stop profiling, and no RAM. It is appropriate for high-precision measurements of narrowly targeted sections of code.
For further discussion of all three profiling methods, refer to the Profiling Nios II Systems section in the Embedded Design Handbook.
The core is designed for use in Avalon® -based processor systems, such as a Nios® II or Nios® V processor system. Intel FPGA device drivers enable the Nios® II or Nios® V processor to use the performance counters.