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Cc: freebsd-net@freebsd.org, Eugene Grosbein <eugen@kuzbass.ru>,
	Robert Watson <rwatson@freebsd.org>, Luigi Rizzo <rizzo@iet.unipi.it>,
	Julian Elischer <julian@elischer.org>
Subject: Re: dummynet dropping too many packets
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Ian Smith wrote:
> On Wed, 7 Oct 2009, rihad wrote:
> 
>  > Robert Watson wrote:
>  > 
>  > > I would suggest making just the HZ -> 4000 change for now and see how it
>  > > goes.
>  > > 
>  > OK, I will try testing HZ=4000 tomorrow morning, although I'm pretty sure
>  > there still will be some drops.
> 
> Even if there are, I'd like to know what (rough) percentage in increased 
> interrupt load you experience with HZ=4000 vs 1000 on that beast in your 
> application, or of any discernable effects on other running processes?
> 

Besides having little (if any) positive effect on the output packet drop 
rate, it runs pretty well, there's no apparent difference, no drop in 
performance etc.

Current interrupt load snapshot as per systat -vmstat:
   Interrupts
  59606 total
        atkbd0 1
        ata0 irq14
    931 mfi0 irq16
        uhci0 uhci
   4001 cpu0: time
  23549 bce0 256
   3118 bce1 257
   3999 cpu3: time
   3999 cpu2: time
   4001 cpu1: time
   4003 cpu4: time
   4003 cpu5: time
   4001 cpu6: time
   4001 cpu7: time