Matthew Dillon wrote: > :This would be very useful for things like network cards which > :could switch from interrupt to polling mode on the fly and get > :better performance with higher load. > > It's hard to how many is too many, but this would certainly be a > benefit to older network cards which do not have interrupt moderation.
Linux network developers have made statements that best results can be achieved always if both - interrupt moderation and adaptive polling (ie. NAPI in Linux) are used. I don't have any pointers to test results though. Note that NAPI isn't just adaptive polling algorithm, but also splitting interrupt work into to parts (hardware interrupt handler and softirq). This might be big contributor to the win from using both in the same time as well. -- Hasso Tepper
