Re: ksoftirqd_CPU0 causing severe latency

[Jim Roland]

How do I profile and collect interrupt info?  I have not tried to do this
w/o iptables, because iptables is required for this box to do what it does.
I'm not a programmer, so looking at eepro100's code will not do me much
good.  :)

----- Original Message -----
From: "Denis Vlasenko" <[e-mail]>
To: "Jim Roland" <[e-mail]>; <[e-mail]>
Sent: Friday, January 10, 2003 3:16 AM
Subject: Re: ksoftirqd_CPU0 causing severe latency

> On 10 January 2003 08:41, Jim Roland wrote:
> > I am running a RH7.2 router with kernel 2.4.18-19.7.x and upgraded
> > from 2.4.18-17 in hopes this would fix the problem, but it hasn't.
> >
> > The problem I am experiencing is that after a while, the system
> > begins to lag badly, and running "ps -ax" writes to a SSH console
> > like a terminal running at 14.4kbps.  This only seems to have
> > occurred after the box started procesing a network load.
> >
> > The box is a router, with a Supermicro (model=?) motherboard with
> > embedded Intel EEpro/100 NICs using the eepro100 module.  This box is
> > also serving as an iptables filter for the network as well.  It's
> > processing approximately 60Mbps sustained traffic outbound, and about
> > 10-15Mbps traffic inbound.
>
> That's not a small figure :)
>
> > The box also lags SEVERLY when I'm trying to use the state matching
> > in the kernel (as module), lagging badly when ip_conntrack is loaded.
> >
> > In contrast, I am running the same OS and kernel versions on another
> > box (same modules) and am not having the same problem (it is only
> > handling about 5Mbps sustained out, and 1Mbps sustained inbound).
> >
> > I need HELP!
>
> Profile your box. (We need to know where it spends most of CPU time).
> Send profile data to the list.
>
> Also collect interrupt rate info.
>
> You may also look into Intel EEpro/100 driver's interrupt handler code.
>
> Does is lag that bad without iptables?
> --
> vda
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