Re: [Xenomai-help] Beginner's question / testsuite / latency

[Philippe Gerum <rpm@xenomai.org>]

On Tue, 2006-08-01 at 15:13 +0200, Gilles Chanteperdrix wrote:
> Julien Heyman wrote:
>  > Some good news from my side :
>  > I did the same on my EPIA box (added Option "NoAccel" in the Device section 
>  > referring to the Trident video driver) and since then the latency test works 
>  > like a charm. Zero overrun, and a stable max value (around 50 microseconds), 
>  > even when I launch multiple heavy applications at the same time.
>  > Display performance has obviously taken a bit hit, but this is not my main 
>  > concern for now.
>  > Thanks for the tip, there is no way I would have figured that one out by 
>  > myself ;)
> 
> Maybe this tip deserves an entry in the TROUBLESHOOTING file?

Indeed. Please commit.

> plain text document attachment (xeno-x-noaccel.diff)
> Index: TROUBLESHOOTING
> ===================================================================
> --- TROUBLESHOOTING	(revision 1403)
> +++ TROUBLESHOOTING	(working copy)
> @@ -218,6 +218,17 @@
>  
>  ______________________________________________________________________
>  
> +Q: I am seeing high latency spots when running under X-window, what 
> +   can I do?
> +
> +A: Try disabling hardware acceleration in the X-window server 
> +   configuration file; in the "Device" section of /etc/X11/XF86Config-4,
> +   add the following line:
> +
> +   Option "NoAccel"
> +
> +______________________________________________________________________
> +
>  Q: Xenomai HAL's initialization fails with error: -1 no such device
>  
>  A: Dumping the kernel message log using "dmesg" will likely give you
-- 
Philippe.