Brian,

Thanks!  That's exactly the type of info I'm looking for.
I've been using a Spirent/SMARTBITS SMB200 to bash any ppc
hardware I can get my hands on in the lab.  But our current
assortment falls either into the low end or the really high
end.  We are working on a new project using an 8245 @400MHz;
of course, the HW is already half baked but new features
keep creeping into the project-- you know the drill. Hence
my queries regarding what the mid range ppc stuff can do.

Thanks and regards.

The performance on 4xx is dependent on how much work
you want to do in the ethernet driver.

A (nearly) stock kernel will be able to forward 64
byte packets at around 15,000 pps on 200MHz 405GP.
The interrupts burn alot of CPU cycles.  If you
implement a timer-based interrupt mitigation scheme
using the FIT timer interrupt to clean out the RX and
TX rings, you will be able to hit about 35K to 40K
pps.  On top of that, you can implement
CONFIG_NET_FASTROUTE in the driver, bypassing most of
the IP stack.  After doing this you will get a maximum
sustained throughput of around 65K pps.

These numbers were measured on a 200MHz 405GP w/
100MHz SDRAM.  The on-chip ethernet was slightly
faster than the 82559.

Large packet performance is not an issue, and you
should be able to saturate the 100mbps link with 1500
byte packets.

Regards,
Brian

quoted

-----Original Message-----
From: linuxppc user [mailto:linuxppc@opqua.com]
Sent: Tuesday, November 25, 2003 8:22 PM
To: linuxppc-embedded@lists.linuxppc.org
Subject: RE: routing performance w/embedded linux on

ppc?

quoted

Stephen,

Thanks for the follow-up.  Do you have any numbers

for "lesser"

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processors than the 750, e.g. the 8245/8240 or the

405GP?

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Thanks again and regards.

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We sustain ~71MB/s routing packets in the

following manner.

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=====[GbE]=====>[BCM5691]==[GbE]==>[MV64360/PPC750FX]
{routing here}

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                                   ||
                                   || [GbE]
                [BCM5691]<==========
                    ||
                    || [GbE]
                    ||

===========>[MV64360/PPC750FX] {destination}

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If you want to see a P4@2GHz+ brought to it's

knees,

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perform a benchmark

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such as nbench and throw 80B packets at it at

~100,000

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packets/s or so.

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An 800MHz PPC750FX/MV64360 combo barely even

showed a

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performance hit

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whether the packets were incoming or not.


Stephen B. Johnson
Sr. Applications Engineer, Global Accounts
Artesyn Communication Products
8310 Excelsior Drive
Madison, Wisconsin 53717

phone  800-356-9602

NASDAQ:  ATSN


-----Original Message-----

Folks,

There seems to be a plethora of data regarding

linux IP routing

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performance (e.g., forwarding rate in packets per

sec) on x86

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platforms.  This is likely because x86 boxen are

all that typical

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university students have in front of them.  :*)

I'm looking for some papers, pointers, or whatever

regarding linux

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routing performance on midrange embedded ppc

hardware, for example

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the moto8245 and ibm405GP (as used inside the

Xilinx Virtex II Pro).

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Basically our application boils down to a 4 port

router, and we'd

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like to get a handle on what kind of aggregate

throughput and pps

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we would be able to handle using these types of

ppc processors at

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~266/300 MHz.  Yes, the 8260, and 7xx, et al, are

faster, but our

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equipment cost profile is very restrictive.

example config:

  i82559 | <- PCI -> [mpc8245 @ 300MHz]
  i82559 |
  i82559 |
  i82559 |

There is other stuff hanging off of PortX and so

forth, but that's

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what the datapath looks like.

Thanks for any leads/hints/ideas/etc.  I'll

summarize back.

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** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/