more interrupts with polling(4) on em(4)

[Gergely CZUCZY]

Good morning,

I've noticed 33K interrupts/sec on an em(4) gigabit interface on
a box. This many interrupts seemed a bit too high, so I thought
I should enable polling(4). After enabling it i've got 55K per
second, even higher.

I've just done "ifconfig em1 polling", and by this the number
of interrupts increased.

options DEVICE_POLLING is in the kernel.

The system is:
FreeBSD lvs1.in.publishing.hu 6.2-RELEASE-p6 FreeBSD 6.2-RELEASE-p6 #2: Fri Jul 27 10:57:50 UTC 2007     toor at pointyhat.in.publishing.hu:/usr/obj/usr/src/sys/LVS  i386


Isn't polling supposed to lower the interrupt load?

What am I doing wrong here? I don't think this is
the expected behaviour, at least, not by me.

Sincerely,

Gergely Czuczy
mailto: gergely.czuczy at harmless.hu

-- 
Weenies test. Geniuses solve problems that arise.
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