On Sunday 07 March 2021 06:43:45 Gene Heskett wrote: > Greetings folks; > > Experimenting with various ways to see if I can find out why the > initial homing is so slow and loaded with windup effects, effects that > do not seem to affect the stepper driven axises. > > It takes at least 5 seconds for it to get up to search speed, and > another 5 seconds to get back to a stop after the home switch has been > found, coasting 20-25 degrees getting stopped, then it goes into latch > speed and takes another minute to get back to the switch edge. And > theres a random offset being applied to the home position in the > linuxcnc dro that does not exist > > The randomness gets obviously worse if I crank up the thread speeds, > and causes a zero drift in the dro readings for repeatedly issuing the > g0a5;g0a-15 while attempting to optimize the servo settings. > > This machine's install is your latest respin of buster. Download, burn > and installed in late december IIRC. > > And rtapi shows up in an htop output, something that isolcpus normally > hides from htop. That got me snooping. > > And there is no mention of isolcpus in /boot/grub/grub.cfg! > > From uname -a: > 4.19.0-14-rt-amd64 #1 SMP PREEMPT RT Debian 4.19.171-2 (2021-01-30) > x86_64 GNU/Linux > > Note the date! > > So, whats the current status of the isolcpus boot parameter? > > Also latency-test will not run, can't find the threads, fast or slow.
And on repeat test, it does run, runs well. But the one remaining atom's latency is horrible, 50+ u-s on both threads, the other 2 i5 dells are in the 4 u-s region. I have another dell i5 to replace it as soon as some 60 degree weather arrives. > So someting is fubared IMO, but what? > > Cheers, Gene Heskett Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
