Maximum NIC interrupts
jfvogel at gmail.com
Wed Dec 26 13:08:58 PST 2007
On Dec 26, 2007 8:10 AM, Nash Nipples <trashy_bumper at yahoo.com> wrote:
> Dear Jordi,
> In theory, on a Gigabit link you get 1 000 000 000 bits * second.
> By default you have the MTU set to 1500 bytes which makes ~12 000 bits.
> 1 000 000 000 / 12 000 = ~ 83 333 packets per second.
> 83 333 packets per second makes 0.083333 packets per microsecond.
> 1 / 0.08333 = 12.0 microseconds per packet. Thus one can interrupt CPU
> at a rate of ~83 333 times per second. If you use lower packets sizes you
> might get even more funny numbers.
> 8000 is a quiet low number. The driver was developed by guys
> at Intel. I don't see a reason to worry.
> By the way they have products with Interrupt Moderation.
Yes, one of the items in my queue is AIM, adaptive interrupt moderation, the
Linux driver has this, my coworker Jesse Brandeburg developed that code, and
I hope to do something similar for the em driver.
Anyway, I'm still on vacation and don't want to distract myself from music,
but look for AIM sometime this new year :)
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