Re: Dropping Packets in 2.6.17

Miquel van Smoorenburg
2006-06-22T14:01:41Z

In article <449A9ADC.9070800@draigBrady.com>,
Pádraig Brady <P@draigBrady.com> wrote:
>Note there is a max interrupt rate of around 80K/s
>on x86 at least (not sure about opteron), so make
>sure you're using NAPI. /proc/interrupts will
>show your interrupt rate.

The e1000 driver has some more knobs you can turn. I have this
in my /etc/modules file:

e1000 RxAbsIntDelay=256,256 TxAbsIntDelay=256,256 TxDescriptors=1024,1024 RxDescriptors=1024,1024

(this is for two cards)

and this in /etc/sysctl.conf:

# Tune back swappiness on 2.6
vm.swappiness = 10

# Lots of kernel memory needed for e1000
vm.min_free_kbytes = 65535

This box accepts ~250 mbit/sec, stores that on disk, and streams it
out again to multiple peers at ~1300 mbit/sec total. Kernel 2.6.14.2,
dual xeon em64t in 64 bits mode, 4 GB memory.

Mike.