Re: [E1000-devel] e1000 linux driver problems

[Brandeburg, J. <jes...@in...>]

popescu claudiu wrote:
> Hi,
>=20
> After some time of googling and reading i can't find a solution to
> high CPU usage on high amount of packets.

what is a high amount of packets?  can you run 'mpstat 5 2' and 'netstat
-i ; sleep 5; netstat -i'

I would like to see interrupts and cpu utilization, as well as packets
per second

<snip good data to have>
> ( i suspect the network cards, maybe they are to old, anyway i am
> configuring a new server, the same like above but with 2x  01:01.0
> Ethernet controller: Intel Corporation 82545GM Gigabit Ethernet
> Controller (rev 04), till then i wanna know what is wrong with the
> actual one )=20

those network cards are old, and I believe that they don't even support
InterruptThrottleRate
=20
> 19:    1255717    7308389  242756519   28949634     eth0
> 20:        100    7306079   34092280  274598160     eth1

> On high traffic the cpus that are assigned for eth0 and eth1 are used
> from 80% to 100% resulting in over 150ms response time isted of 1ms
> from a computer connected to the same switch as the server.

with NAPI, and high traffic loads it is expected that CPU utilization
when polling will be 100% on that cpu.  That is pretty much normal.
=20
> I am using Gentoo 2007.0 always up to date, running services on this
> server: bgpd ( 4200 routes in total ), named, dhcp ( about 800 macs )
> and iptables ( 1700+ rules ).
> I don't think my problem is from this services, i suspect a high
> amount of packages sent by virused computers connected to my local
> network or something like this.
> I am using irqbalance daemon from irqbalance.org insted of the kernel
> irqbalance, the e1000 driver is 7.6.9 installed with NAPI enabled and
> the module was loaded with modprobe e1000
> InterruptThrottleRate=3D20000,20000=20

why did you choose InterruptThrottleRate=3D20000?  that is a pretty high
interrupt rate.  In addition, 82543 does not support the interrupt
throttle rate register (82545 does).  That is probably a bug in our
driver that we don't print anything to let the user know the parameter
did nothing.

for 82543gc, you will need to play with RxIntDelay and TxIntDelay, and
maybe RxAbsIntDelay and TxAbsIntDelay parameters, increasing these
values will decrease your interrupt rate.

for your information, 82543 is from year 2000, and doesn't support
PCI-X, nor InterruptThrottleRate.

Jesse