On Sun, Aug 11, 2013, at 06:02 PM, Charles Steinkuehler wrote:
> On 8/11/2013 4:22 PM, sam sokolik wrote:
> > At the fest when they where working on the mazak - Jeff E was 
> > alt-tabbing between 2 windows and the machine was going Thud - Thud - 
> > Thud each time.  (finally JMK yelled at him to stop :) )  They went to 
> > the 2nd hand computer store and bought a video card and the problem was 
> > solved.  (not that you have that option...)
> 
> Interesting...for RTAI or Xenomai, <alt><tab> should not be able to
> bring the system down like that, unless there's something going on with
> SMI (the only thing AFAIK that can run at a lower level than RTAI or
> Xenomai on an x86 system).  If this was on a preempt-rt system, that
> behavior is totally understandable.
> 
> It is possible the <alt><tab> problem could represent the same issue I
> am seeing on the ARM.
> 

The alt-tab thing that Sam is talking about was from ages ago.  This
was at the first CNC workshop at Cardinal Engineering.  Maybe 2007
or so?  Long before RT-PREEMPT or Xenoami.

That particular system had a graphics card with an unfriendly driver.
Doing an alt-tab window switch apparently resulted in some large
bit-blt transfers being done using DMA, and they locked the bus for
the duration, so the RT stuff got stalled.  As Sam said, we went
into town and got a Matrox Millennium at the used computer store
for $5, and all was good.


-- 
  John Kasunich
  [email protected]

------------------------------------------------------------------------------
Get 100% visibility into Java/.NET code with AppDynamics Lite!
It's a free troubleshooting tool designed for production.
Get down to code-level detail for bottlenecks, with <2% overhead. 
Download for free and get started troubleshooting in minutes. 
http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
_______________________________________________
Emc-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-developers

Reply via email to