Measure user/kernel space crossing overhead¶
This repo can help us to measure the pure user/kernel space crossing overhead in CPU cycles.
The mechanism is described in its README. Check it out!
Some quick takeaways:
- It ain’t cheap! It usually take ~400 cycles from user to kernel space.
- User-to-kernel crossing is more expansive than kernel-to-user crossing!
- Virtilization adds more overhead