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* Tyan S2466 MPX integrated ethernet interrupt happy
@ 2002-03-22 22:29 Shane Nay
  2002-03-23  1:53 ` Andrew Morton
  2002-03-23  3:22 ` Bill Davidsen
  0 siblings, 2 replies; 4+ messages in thread
From: Shane Nay @ 2002-03-22 22:29 UTC (permalink / raw)
  To: linux-kernel

I have an S2466 with an integrated 3COM 3C905C ethernet controller.  
What I've noticed when streaming tons of data accross my internal LAN 
is that the ethernet driver appears to be sucking up tons of cycles.

A quick investigation of /proc/interrupts shows-
  0:     195949     192414    IO-APIC-edge  timer
  1:       5126       5129    IO-APIC-edge  keyboard
  2:          0          0          XT-PIC  cascade
  5:          0          0   IO-APIC-level  usb-ohci
  8:          1          0    IO-APIC-edge  rtc
  9:    4248819    4245969   IO-APIC-level  eth0
 10:     144865     145243   IO-APIC-level  usb-ohci, nvidia, EMU10K1
 12:      48546      48865    IO-APIC-edge  PS/2 Mouse
 14:     122395     121652    IO-APIC-edge  ide0
 15:      26286      26498    IO-APIC-edge  ide1
NMI:          0          0 
LOC:     388204     388212 
ERR:          0
MIS:          4


So, approximately 8.5 million ethernet interrupts.  The system is 
noticably slower when streaming ethernet data, and it's sucking up a 
lot more processing time than on my other much slower other box.  
This box is running a stock 2.4.18 kernel from kernel.org (i.e. no 
custom hacks).  It's running 2 1800+ XPs.

I'm wondering if anyone has seen this and has a quick solution.  If 
not I'll take a look through the 3com code when I get back from 
vacation next Sunday.  (Leaving in a few hours)

Thanks,
Shane Nay.

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Tyan S2466 MPX integrated ethernet interrupt happy
  2002-03-22 22:29 Tyan S2466 MPX integrated ethernet interrupt happy Shane Nay
@ 2002-03-23  1:53 ` Andrew Morton
  2002-03-23 13:45   ` Shane Nay
  2002-03-23  3:22 ` Bill Davidsen
  1 sibling, 1 reply; 4+ messages in thread
From: Andrew Morton @ 2002-03-23  1:53 UTC (permalink / raw)
  To: Shane Nay; +Cc: linux-kernel

Shane Nay wrote:
> 
> I have an S2466 with an integrated 3COM 3C905C ethernet controller.
> What I've noticed when streaming tons of data accross my internal LAN
> is that the ethernet driver appears to be sucking up tons of cycles.
> 
> A quick investigation of /proc/interrupts shows-
>   0:     195949     192414    IO-APIC-edge  timer
>   1:       5126       5129    IO-APIC-edge  keyboard
>   2:          0          0          XT-PIC  cascade
>   5:          0          0   IO-APIC-level  usb-ohci
>   8:          1          0    IO-APIC-edge  rtc
>   9:    4248819    4245969   IO-APIC-level  eth0
>  10:     144865     145243   IO-APIC-level  usb-ohci, nvidia, EMU10K1
>  12:      48546      48865    IO-APIC-edge  PS/2 Mouse
>  14:     122395     121652    IO-APIC-edge  ide0
>  15:      26286      26498    IO-APIC-edge  ide1
> NMI:          0          0
> LOC:     388204     388212
> ERR:          0
> MIS:          4
> 
> So, approximately 8.5 million ethernet interrupts.  The system is
> noticably slower when streaming ethernet data, and it's sucking up a
> lot more processing time than on my other much slower other box.
> This box is running a stock 2.4.18 kernel from kernel.org (i.e. no
> custom hacks).  It's running 2 1800+ XPs.

That all looks normal.  Could you be more specific about
the performance problems?  How much slower? Output from
`top' and `ps'?  Any nasty messages in the system log?

Looking at the ethernet driver won't help, I expect - it's
as efficient as most any other driver.  If there is a problem,
it lies elsewhere...

A kernel profile would be illuminating.  Build the kernel with as few
modules as possible, boot the machine with `profile=1' and play
with readprofile.

-

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Tyan S2466 MPX integrated ethernet interrupt happy
  2002-03-22 22:29 Tyan S2466 MPX integrated ethernet interrupt happy Shane Nay
  2002-03-23  1:53 ` Andrew Morton
@ 2002-03-23  3:22 ` Bill Davidsen
  1 sibling, 0 replies; 4+ messages in thread
From: Bill Davidsen @ 2002-03-23  3:22 UTC (permalink / raw)
  To: Shane Nay; +Cc: linux-kernel

On Fri, 22 Mar 2002, Shane Nay wrote:

> I have an S2466 with an integrated 3COM 3C905C ethernet controller.  
> What I've noticed when streaming tons of data accross my internal LAN 
> is that the ethernet driver appears to be sucking up tons of cycles.

The table is just the number of ints, see below for one of my boxen which
is running 200-250 users and has idle of ~92% over three days.
 
> A quick investigation of /proc/interrupts shows-
>   0:     195949     192414    IO-APIC-edge  timer
>   1:       5126       5129    IO-APIC-edge  keyboard
>   2:          0          0          XT-PIC  cascade
>   5:          0          0   IO-APIC-level  usb-ohci
>   8:          1          0    IO-APIC-edge  rtc
>   9:    4248819    4245969   IO-APIC-level  eth0
>  10:     144865     145243   IO-APIC-level  usb-ohci, nvidia, EMU10K1
>  12:      48546      48865    IO-APIC-edge  PS/2 Mouse
>  14:     122395     121652    IO-APIC-edge  ide0
>  15:      26286      26498    IO-APIC-edge  ide1
> NMI:          0          0 
> LOC:     388204     388212 
> ERR:          0
> MIS:          4

newssvr17:twister$ cat /proc/interrupts 
           CPU0       CPU1       
  0:   14112007   14110727    IO-APIC-edge  timer
  1:        473        467    IO-APIC-edge  keyboard
  2:          0          0          XT-PIC  cascade
  8:          0          1    IO-APIC-edge  rtc
 12:        104        105    IO-APIC-edge  PS/2 Mouse
 14:          3          2    IO-APIC-edge  ide0
 18:   88268186   88280808   IO-APIC-level  eth0
 20:    6655721    6658714   IO-APIC-level  ips
 27:   74212944   74213812   IO-APIC-level  PCnet/FAST III 79C975
 28:         14          2   IO-APIC-level  aic7xxx
 29:         10          6   IO-APIC-level  aic7xxx
NMI:          0          0 
LOC:   28223102   28223059 
ERR:          0
MIS:          0

-- 
bill davidsen <davidsen@tmr.com>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Tyan S2466 MPX integrated ethernet interrupt happy
  2002-03-23  1:53 ` Andrew Morton
@ 2002-03-23 13:45   ` Shane Nay
  0 siblings, 0 replies; 4+ messages in thread
From: Shane Nay @ 2002-03-23 13:45 UTC (permalink / raw)
  To: Andrew Morton; +Cc: linux-kernel


> > So, approximately 8.5 million ethernet interrupts.  The system is
> > noticably slower when streaming ethernet data, and it's sucking
> > up a lot more processing time than on my other much slower other
> > box. This box is running a stock 2.4.18 kernel from kernel.org
> > (i.e. no custom hacks).  It's running 2 1800+ XPs.
>
> That all looks normal.  Could you be more specific about
> the performance problems?  How much slower? Output from
> `top' and `ps'?  Any nasty messages in the system log?

No nasties in the syslog.  System usage from top averages 50% per 
CPU.  (By system I mean kernel usage, bounces between 70 and 30 per 
CPU)

> Looking at the ethernet driver won't help, I expect - it's
> as efficient as most any other driver.  If there is a problem,
> it lies elsewhere...

Gotcha, yes that could definetly be.  This was extraordinarily 
unscientific.  I was thinking maybe someone had seen something else 
like this on this platform.  So, I'll write a test that isolates 
ethernet from other stuff like ide performance, etc.

> A kernel profile would be illuminating.  Build the kernel with as
> few modules as possible, boot the machine with `profile=1' and play
> with readprofile.

Will do when I return.

Thanks,
Shane Nay.
(Someone else noted their /proc/interrupts for the same machine, but 
my box had only been up for 1.5 hours :)

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2002-03-23 13:44 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2002-03-22 22:29 Tyan S2466 MPX integrated ethernet interrupt happy Shane Nay
2002-03-23  1:53 ` Andrew Morton
2002-03-23 13:45   ` Shane Nay
2002-03-23  3:22 ` Bill Davidsen

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