JIT Stopwatch

[Lichtso]

Counts CPU cycles by lfence ; rdtsc ; lfence

[dmakarov]

This is nice, but wouldn't it be simpler to instrument the map method MemoryRegions

rbpf/src/memory_region.rs

Line 144 in 134c217

pub fn map<E: UserDefinedError>(

by inserting a call to time::Instant::now() at the entrance to the function and at the exit from it?

[Lichtso]

That would only work for the Interpreter.
The JIT has to do a context switch to Rust and back, which is expensive and should be included in the measurement I think.

[dmakarov]

That would only work for the Interpreter.
The JIT has to do a context switch to Rust and back, which is expensive and should be included in the measurement I think.

ok, makes sense. Yes, context switch should be accounted for as part of the address translation overhead in this case.