This is the mail archive of the ecos-discuss@sources.redhat.com mailing list for the eCos project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: ethernet performance <TCPIP guru question>


On Thu, 2002-04-25 at 01:45, Roland Caßebohm wrote:
> On Thursday, 25. April 2002 03:39, Gary Thomas wrote:
> > I've tested TCP operations with eCos, using 100Mb interfaces, and I get
> > transfer rates of around 8Mbytes/sec (Linux host, sending data to an
> > eCos application which simply sinks the data).
> >
> Which platform did you use? I have done the same with eCos on a Celeron 400 
> MHz with 82559 ethernet card and have the same performance.
> But on an ARM7TDMI 50 MHz board (SNDS 100) with also 100 MBit I get only 600 
> kByte/s. Is this because of the slower processor or does is there problem?
> 

This particular test was between two similar P-II/400 MHz PC systems, 
using 82557 PCI ethernet controllers on both systems, on an isolated 
100Mb router/switch.

> Maybe somebody have allthough experience ARM7TDMI and 100 MBit ethernet and 
> could tell me which max. data transfer rate he have?

I don't have 100Mb on an ARM7, but on a 50MHz SA110 (pretty similar), 
using the same 82557 ethernet controller, I only got about 2MBytes/sec.
Thus, yes, the processor speed has a lot to do with the performance.
Also, the actual ethernet controller will have a large influence.  The 
82557 does high speed DMA to get at the packets, etc.  Some others 
(notably the Crystal CS8900) are programmed I/O and *very* slow.


--
Before posting, please read the FAQ: http://sources.redhat.com/fom/ecos
and search the list archive: http://sources.redhat.com/ml/ecos-discuss


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]