[POLLING] strange interrupt/system load

[rihad]

Bruce Evans wrote:
> On Sat, 12 Sep 2009, rihad wrote:
> 
>> The box experiences ~230 mbit/s traffic flow through it. I've doubled 
>> some sysctls after reading polling(4):
>> kern.polling.each_burst=10 # was: 5
>> kern.polling.burst_max=350 # was: 150
>>
>> FreeBSD 7.2-RELEASE-p3 amd64
>> HZ=1000
> 
> How much better does it work without POLLING?
> 
Without polling (current load around 190-200 mbit/s, around 24-26 kpps):

top:
CPU:  0.0% user,  0.0% nice,  8.4% system,  0.0% interrupt, 91.6% idle

Interrupts/s: 18322 total
28 mpt0 irq16
1999 cpu0: time
6906 em0 irq256
3392 em1 irq257
1999 cpu1: time
1999 cpu2: time
1999 cpu3: time