[plug] What's "too much work at interrupt"?

[Peter F Bradshaw]

Hi;

On Tue, 7 Sep 2004, Bernd Felsche wrote:

> On Tuesday 07 September 2004 15:27, Craig Ringer wrote:
> > On Mon, 2004-09-06 at 11:41, Bernd Felsche wrote:
> > > I'm getting kernel messages when trying to copy files over a network:
> > >
> > > 	eth1: Too much work at interrupt, IntrStatus=0x0001.
> > > 	eth1: Too much work at interrupt, IntrStatus=0x0001.
> > > 	eth1: Too much work at interrupt, IntrStatus=0x0040.
> > > 	eth1: Too much work at interrupt, IntrStatus=0x0040.
> > > 	eth1: Too much work at interrupt, IntrStatus=0x0040.
> > > 	eth1: Too much work at interrupt, IntrStatus=0x0040.
> > > 	eth1: Too much work at interrupt, IntrStatus=0x0041.
> > >
> > > What could be causing those?
>
> > I've seen that before with a faulty NIC ; a replacement NIC did the
> > trick nicely. Of course, that does not mean that's the only possible
> > reason.
>
> > It seems to me that you've omitted some rather important information,
> > like what hardware eth1 is, what the driver and version is, what the
> > kernel version is, and what the main system hardware is.
>
> It started happening "suddenly". I've upgraded to the latest
> available kernel but the problem persists.
>
> Kernel is 2.4.21-241-athlon (SuSE Linux 8.1)
>
> 8139too Fast Ethernet driver 0.9.26
> eth1: RealTek RTL8139 Fast Ethernet at 0xe4c520 00, 00:20:ed:45:fc:b6, IRQ 11
> eth1:  Identified 8139 chip type 'RTL-8139C'
> eth1: Setting 100mbps full-duplex based on auto -negotiated partner ability 45e1.
>
> It's on the mainboard; Gigabyte GA-7N400Pro (IIRC!)
>
> There's another NIC plugged in that gets to be eth0:
>
> de4x5.c:V0.546 2001/02/22 davies at maniac.ultranet.com
> eth0: DE450-CA at 0xd400 (PCI bus 0, device 10) , h/w address 00:00:f8:00:73:1b,
> eth0: media is BNC.
>
> I hope that the mainboard hasn't been zapped.

>From the above log O/P you are getting receive interrupt overuns. And
the 0x0040 status means that you are getting status fifo overuns as
well. There's a remote chance that some other device is turning off
the interrupt system long enough to cause this. Years ago the the
ATA drivers used to turn off the interrupts for a rather longish time.
I don't kown what the status of these drivers is now but hdparm is your
friend.

Also try and rearrange you PCI interrupts (although that would not
explain why it started suddenly).

There's also a remote chance that the machine on the other end of the
wire is doing something to cause a lot of interrupts on this machine.

My money is on the NIC over the PIC. Chances are that a PIC problem
would cause problems for other devices as well.

Cheers

-- 
Peter F Bradshaw, pfb at exadios.com, ICQ 75431157 (exadios).
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