Previously, I talked about dynamips and how to run Cisco hardware virtually. I also talked about an “idle-pc” value that you needed to compute in order to reduce the CPU usage of dynamips.
Let’s try to compute this value:
- Start dynamips with your IOS image and an empty configuration.
- Wait for the “Press RETURN to get started!” Prompt, and do NOT press enter.
- Wait some time (5-10secs) and press “Ctrl-] + i”. Some statistics will be generated during 10 seconds.
- You will then see an output such as this one:
Please wait while gathering statistics... Done. Suggested idling PC: 0x80340d80 (count=27) 0x80623c00 (count=31) 0x8061de94 (count=29) 0x8061dea8 (count=41) 0x8061e078 (count=39) 0x8061e3c0 (count=47) 0x8061e3e8 (count=25) 0x8061e3ec (count=46) 0x8061e414 (count=40) 0x8061e43c (count=48) Restart the emulator with "--idle-pc=0x80340d80" (for example)
- Just try to relaunch dynamips with theses values of –idle-pc, If you have found the correct one, and idle router should use between 5 and 15 percent of your CPU..
- Keep this value preciously 😉