By the way, I just checked from a backup of my Lucid configuration, and it is not using the second core for anything as well. It just has better latency to begin with.
Ray --J. Ray Mitchell Jr. jrmitche...@gmail.com (818)324-7573 The dogmas of the quiet past, are inadequate to the stormy present. The occasion is piled high with difficulty, and we must rise with the occasion. As our case is new, so we must think anew and act anew. We must disenthrall ourselves, and then we shall save our country.*Abraham Lincoln <http://www.quotationspage.com/quotes/Abraham_Lincoln/>*, *Annual message to Congress, December 1, 1862* *16th president of US (1809 - 1865)* On Sat, Oct 17, 2015 at 2:10 PM, jrmitchellj . <jrmitche...@gmail.com> wrote: > On modern linux kernels, and especially on an RTOS kernel, there are ways > to assign tasks to specific cores of a multicore system. > Affinity is one way that I have used on a project that had data coming in > from DAQ cards at a rapid rate, and I don't want to loose any samples. So > I assigned the data collection to one core, then the processing & packaging > is done on the other core. > > Most of the real time stuff that is currently in kernels is from the > RT-Preempt RTOS project. A news article I saw recently states that more of > it will be brought into the mainline kernel in the near future. > > It really seems weird to me that if you isolate a core from the standard > kernel scheduler, that you are not scheduling task on it with the RTAI > kernel patch. > > Ray M. > > --J. Ray Mitchell Jr. > jrmitche...@gmail.com > (818)324-7573 > > > The dogmas of the quiet past, are inadequate to the stormy present. The > occasion is piled high with difficulty, and we must rise with the occasion. > As our case is new, so we must think anew and act anew. We must disenthrall > ourselves, and then we shall save our country.*Abraham Lincoln > <http://www.quotationspage.com/quotes/Abraham_Lincoln/>*, *Annual message > to Congress, December 1, 1862* > *16th president of US (1809 - 1865)* > > On Sat, Oct 17, 2015 at 1:31 PM, Karlsson & Wang < > nicklas.karls...@karlssonwang.se> wrote: > >> > Since Lucid has reached end of support I decided to back up my config >> and >> > install from the 2.7 live CD. >> > Having done that, installed all of the updates, and adjustments to my >> > config files,I ran the latency test. >> > Overall the latency numbers are 30% higher than the Lucid install, but >> > still in an acceptable range. >> > Setting "isolcpus=1" in grub has no effect on latency, as it did in the >> > Lucid install. >> > Now when I run LinuxCNC, I am getting RTAPI error on startup >> > intermittently. When it does start without the error, the error shows >> up >> > within 5 to 10 minutes. >> > >> > Attached are the dmesg, and the -v startup for linuxcnc. >> > >> > Watching the system monitor while LinuxCNC is running for spikes in the >> CPU >> > utilization shows nothing unusual, other than the second cpu is not >> being >> > utilized at all. >> > I have always thought that isolating a cpu from the linux scheduler was >> to >> > allow the RTAI kernel to use it without the system interrupts >> interfering >> > with it. >> > >> > Is there some setup that i missed to mask the RTAI kernel to use the >> > isolated cpu? Or are there any "taskset" statements that need to be >> changed >> > to properly utilize the isolated cpu? >> > >> > I know just enough about real time OSes to be really dangerous! >> > >> > Any help is always appreciated! >> > >> > --J. Ray Mitchell Jr. >> > jrmitche...@gmail.com >> > (818)324-7573 >> >> If there are more than one core one serve the interrupts and the second >> is used for real time scheduling? >> >> >> ------------------------------------------------------------------------------ >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > > ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
