Hello
is there a way to find out how many times a userspace program is forced to
context switch due to a hardware interrupt?
The reason for this:
I am measuring the retired instruction count of programs using performance
counters (perfmon2 patchset), and trying to find out where the
descrepancies compe from.
On x86, it seems to be:
reported_count = expected_count + 1*major_pagefaults + \
1*hardware_interrupts + known_errata + 1
I can get the pagefault info from getrusage(). The hardware_interrupts
count is my best guess at what is causing the rest, based on the LOC
field in /proc/interrupts. That's not per-process though.
Is this info available? If not, is it possible to patch the kernel to
make it so?
Thanks for any help
Vince
[email protected]