RE: [ECOS] Network speed very slow with redboot

[Gary Thomas <gthomas@redhat.com>]

On Thu, 2002-03-07 at 08:01, Nejat Tek wrote:
> 
> Hello all,
> 
> Now we know that it is supposed to be slow, is there any quick fix
> that can speed up the redboot networking?
> Do you think, for example, polling the ethernet device driver more
> often, or, changing background networking thread priority, can I
> obtain a significant improvement ? If so, which piece of code should
> I play with ?
> 

There are no threads in RedBoot :-)

I don't think that there is much that can be done [easily].  The biggest
problem is the size of the packets that GDB uses and the associated
overhead.  If you use RedBoot to download code directly (using TFTP and
the 'load' command), you'll see much faster download times.  I just tested 
it on one of our platforms here and the difference was pretty
large:
  GDB - 153k (bits/sec)
  RedBoot via 'load' - 700k (bits/sec)
So the problem is not really with RedBoot's networking code, but the
additional overheads involved with the GDB protocol.

> Thanks in advance,
> Nejat Tek
> 
> 
> 
> -----Original Message-----
> From: ecos-discuss-owner@sources.redhat.com
> [mailto:ecos-discuss-owner@sources.redhat.com]On Behalf Of Gary Thomas
> Sent: Thursday, March 07, 2002 8:53 AM
> To: Roland Caßebohm
> Cc: Douglas Bush; eCos Discussion
> Subject: Re: [ECOS] Network speed very slow with redboot
> 
> 
> On Thu, 2002-03-07 at 01:58, Roland Caßebohm wrote:
> > On Tuesday, 5. March 2002 17:19, Douglas Bush wrote:
> > > I have the same performance issue with the EP7211.  My download rate is
> > > 38kbit/s over a 10M Ethernet.  My download rate with the May 2001
> > > redboot image for the EDB7xxx was generally over 380kbit/s.
> > >
> >
> > Hi,
> >
> > the only think i have found is, that the cache wasn't enabled. But enable
> the
> > cache doesn't change much. The download rate is now 200 kbit/s. Is this
> > normal?
> >
> 
> Those are the sort of rates that we see on many boards.  There are a number
> of factors which influence the speed here.  Most RedBoot ports run from
> FLASH
> which is often slow.  Also, the network stack used by RedBoot was designed
> to
> be as simple and small as possible, not necessarily as fast as possible.
> Also,
> GDB sends relatively small packets while downloading.  This adds a lot of
> overhead.
> 
> > Douglas,
> > you sad you have the same problem sins may 2001. I had tried to find
> > something that was changed in this time at the cvs tree. By now I haven't.
> :-(
> 
> AFAIK there have not been any significant changes in this area in the last
> year,
> only minor tweaks and various ports.
> 
> 
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> 
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