[LinuxPPS] rt?

[Bernhard Schiffner]

On Wednesday 25 March 2009 19:05:07 Hal V. Engel wrote:
> I have been running with an rt kernel now for about a day and a half and I 
> have learned some things about how this affects time keeping.
> 
...
> 
> It appears that when using a non-rt kernel that there is a significant amount 
> of variation in the latency of the PPS interrupt handler when the machine is 
> under varying loads.  Using the rt kernel with the serial device running at 
> high priority seems to improve the consistency of the PPS interrupt handler 
> and this does result in a very noticeable improvement in the consistency of 
> the time keeping on a machine with a varying load.  Frankly I am very 
> surprised that I saw this much improvement.   I will definitely continue to 
> run an rt kernel on my workstation and I think it is worthwhile for others to 
> test this type of setup although it may only be of benefit under some 
> circumstances.
> 
> Hal 
> 

Thanks Hal,

it's always a good thing to have something _done_.
You have your expereinces now, we have someone to point to.

And linux (the kernel) will be in a not so distant future rt-capable.
(Thanks to Thomas, Ingo, Steven.)

Bernhard