Re: device polling and weird timer interrupt count from vmstat

3) Is timer int really generated on each cpu? Am i really wasting cpu
time on ~4000 ints per second?

4000 ints per second is rather nothing on any modern CPU.
Have a look at the top(1) display of an otherwise idle
system. The "%interrupt" column should be zero, even if
it's processing 4000 timer interrupts per second. As far
as I know, the cpu timer interrupt handler is very light-
weight.


Thank you for the answer. My convern is that with 4 CPUs i get 8000 ints/second.
While em generates only about 200 ints/second. As i undertand not all int handlers
are the same. Some are heavy and some are light on CPU. So, the question is
what is better (better=less CPU time): 8000 ints/sec from timer or 200 ints/sec from NIC?

--
Regards,
Artem
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