here is a shot of linuxcnc running a 30us base period. You can see the
jitter on this analog scope.
http://electronicsam.com/images/matsuura/20170712_130107.jpg
Using parport resest (5us). So theoretically you could run close to
30khz with rt_preempt on this system (3rd gen i5).
sam
(scope isn't calibrated very good)
On 7/4/2017 10:15 PM, Jon Elson wrote:
On 07/04/2017 05:22 PM, sam sokolik wrote:
Well - I have been playing with debian stretch and 4.9.0-3-rt
kernel. I booted our matsuura (j1900 quad core) which with no
tweeking has aprox 100us latency. (it has been running mesa ethernet
cards with rt_preempt - no issues) Next I booted it with some kernel
line tweaks. (checking the hardware - processors 0,1 and 2,3 share
cache. So I added
isolcpus=2,3 idle=poll
The latency on this system was phenomenal. It has been running for
hours now and still <6us
6 us is quite good, although RTAI can do better on some boxes. But, 6
us is probably good for most interfaces.
Jon
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users
