RE: [uClinux-dev] uCLinux stability on NET+ARM

From: Abhishek Thakur (Abhishek.Thakur@synchronous.net)
Date: Sat Sep 22 2001 - 17:16:22 EDT


Hi Charles,
   Restarting on your thread, as now I too am finding this issue as a
bottleneck. Trying to flood ping the NET+Lx board is causing the kernel to
just hang when 'ps' is done.
   With decently high network load, 'ps' crases on us occassionaly.
   Have you made any progress on the same?
   I tried to go through ps code (hardly 100 line sof code) and could not
find the cause of problem. The fact that the kernel freezes => that the
fault lies 
  - either in the /proc filesystem implementation 
  - or the code handling ethernet i/f at low level (DMA etc.)
   I have been trying to port UCD-SNMP which uses /proc/net/xxx for
information about the network related attributes - and the system freezes
once in a few tries - even without 'ps' being used.
   The irritating part is absence of crash report. I tend to believe that
either the 'DMA part of ethernet driver' or the '/proc filesystem
implementation' is the cause of trouble. but then i don't have much
knowledge on linux kernel - and it would be great if someone more
knowledgeble was there to provide her/his inputs.

   BTW we are using NET+Lx on our own board - quite similar to developer
board - with 2.0.38-1pre7arm kernel.

regards
Abhishek

> -----Original Message-----
> From: Charles Steaderman [mailto:charlies@poliac.com]
> Sent: Wednesday, August 15, 2001 12:40 PM
> To: uclinux-dev@uclinux.org
> Subject: Re: [uClinux-dev] uCLinux stability on NET+ARM
> 
> 
> If you really want to stress the kernel, flood ping the 
> uClinux box (ping -f -s
> 3000 x.x.x.x). The type ps from the console shell on the 
> uClinux box. On our
> NetSilicon development box (as well as our hardware) the 
> kernel will panic and
> lock up after a few ps commands. Please try this and let me 
> know what you find.
> We have discovered other lockup conditions in the NET+ARM 
> ethernet controller as
> well as a DMA transfer problem in the NET+ARM CPU related to 
> the SWAP assembly
> instruction. Still waiting for updates from NetSilicon 
> although I am not holding
> my breath :-)
> 
> - Charlie
> 
> Quoting Giuseppe Colucciello <Jcolucciello@cfl.rr.com>:
> 
> > Charles,
> > 
> > I have been using Net-Lx for the past 3 months and we are running an
> > http server (thttp) on it and seems to be quite stable and 
> reliable. I
> > am
> > currently porting UpNp (Universal Plug and Play) from the OpenSource
> > SDK and finding few problems with the compiler 
> (arm-uclinux-g??), but I
> > think
> > they are specific to the way the macros are formulated in the UpNp
> > code...
> > Stable, I think is as stable as most of the other micros implemented
> > (ported)
> > out there,,,
> > My 2 cents (for now)
> > -G
> > 
> > ----- Original Message -----
> > From: "Charles Steaderman" <charlies@poliac.com>
> > To: <uclinux-dev@uclinux.org>
> > Sent: Wednesday, August 15, 2001 10:55 AM
> > Subject: [uClinux-dev] uCLinux stability on NET+ARM
> > 
> > 
> > > Has there been any progress on the stability of uCLinux on the
> > NetSilicon
> > > NET+ARM CPU? I haven't seen anything posted for quite a 
> while since
> > we
> > posted
> > > this problem to NetSilicon 6 months ago. Crashing the OS by flood
> > pinging
> > and
> > > typing ps from the console doesn't give me a "warm and 
> fuzzy" feeling
> > about the
> > > robustness of the NET+ARM port. Any information (or 
> suggested places
> > for
> > me to
> > > look) are welcomed. BTW, I do not know the ARM 
> architecture very well,
> > but
> > I am
> > > willing to help solve this problem in any way that I can.
> > >
> > > --
> > > charlies@poliac.com
> > > Charles Steaderman
> > > VP Engineering
> > > Poliac Research Corporation
> > > (V) 952.707.6245
> > > (M) 612.242.6364
> > > This message resent by the uclinux-dev@uclinux.org list server
> > http://www.uClinux.org/
> > >
> > 
> > This message resent by the uclinux-dev@uclinux.org list server
> > http://www.uClinux.org/
> > 
> 
> 
> 
> --
> charlies@poliac.com
> Charles Steaderman
> VP Engineering
> Poliac Research Corporation
> (V) 952.707.6245
> (M) 612.242.6364
> This message resent by the uclinux-dev@uclinux.org list 
> server http://www.uClinux.org/
> 

This message resent by the uclinux-dev@uclinux.org list server http://www.uClinux.org/


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