Hi, Is there any way to measure interrupt latency ( delay between interrupt occurred and interrupt service routine is getting called) in VM.
Consider a device is assigned to a VM (using passthrough). Now, interrupt is triggered for the device. I believe kernel code in Host side is getting called first and then corresponding interrupt handler registered in Guest side is getting called. Now , I would like to measure the latency between a. interrupt notification at host side b. Actual interrupt handler called at Guest side Is there a (software)method exists to measure interrupt latency for a device inside VM.? Architecutre : X86_64 and qemu-kvm used. PS: I read about using some high precision timer and measure time difference. But I am not sure whether it is possible to access the timer from Host and Guest and measure the latency. Please let me know. Thanks
