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[03:18:17] <DomCa> Hi everyone! I recently installed LinuxCNC and tried to tune for latency on an Athlon64 X2 system. That worked quite well. I am measuring latency with the hal-histogram while running the axis simulated machine and milling the LinuxCNC logo. I get max. latencies of about 15.000. I also noticed that with isolcpus=1 only core 0 is used exclusively for everything. However I then started experimenting with "taskset 0x2 <pid of Linuxc
[03:18:44] <DomCa> Moving the "millingtask" I could reduce the latency to about 10.000.
[03:19:13] <DomCa> I now wanted to ask if anyone here has some experiency with the different tasks and scheduling them to different cores.
[03:20:00] <DomCa> I am getting a new coreI5 system soon and thought that I might isolate only two cores and then run the GUI tasks on one and the realtime tasks on the other.
[03:20:15] <DomCa> Right now I have to manually move the tasks. Could this be automated?
[03:30:44] <archivist> DomCa, are you building a very fast servo or a normal system
[03:36:19] <DomCa> normal parport system with steppers. I am just curious and want to tune to the max. And I also want to use the other cores in the corei5 (isntead of totally isolating 3 of 4) to get better response for the other applications
[03:37:48] <archivist> I run steppers systems at 15k fast enough for most things
[03:40:25] <DomCa> I will also start with my LinuxCNC as it is now. However, with the new coreI5 I would realy like to use the other cores.
[03:40:31] <DomCa> Since the number of tasks of LinuxCNC is relatively low, I can then try to shift them manually and see the results.
[06:42:01] <skunkworks> zlog
[06:48:26] <skunkworks> pcw_home, for grins I plugged the hard drive into an old 330 atom.. It probably would run 1khz.. It has the moving mouse issue - following error goes way up when you move the mouse.
[09:35:09] <pcw_home> skunkworks yes the atoms have decent latency test results but lousy real timing when doing I/O
[09:35:54] <skunkworks> pcw_home, would the dpll help?
[09:36:05] <skunkworks> well - my normal good running setup?
[09:36:19] <pcw_home> might be interesting to try your config with DPLL and see
[09:36:46] <skunkworks> Do I need a different bit file? or Do I need to set something up? I didn't see any dpll pins
[09:40:54] <skunkworks> The way I read the hostmot2 page - they should be enabled
[09:41:38] <pcw_home> Yes it needs a different bit file
[09:41:39] <pcw_home> The DPLL is installed be default in Ethernet configs and any config needing pre-triggers like absolute encoders
[09:41:41] <pcw_home> but not normally in standard PCI/EPP configs
[09:42:37] <skunkworks> ok
[09:43:05] <skunkworks> heh - I think I meant 50000 for I but I typed in 500000...
[09:43:08] <skunkworks> http://electronicsam.com/images/KandT/testing/emco/emcofollong3.png
[09:46:25] <pcw_home> the DPLL might help noticebly on a system with bad latency
[09:47:29] <pcw_home> building a DPLL version now... (just one copy paste source line different)
[09:57:57] <pcw_home> http://freeby.mesanet.com/5i25_SKUNKWORKS_PWMD.bit
[10:15:11] <skunkworks> pcw_home, Thank you!
[17:11:51] <KGB-linuxcnc> 03Dewey Garrett 05dgarr/external_offsets 96a9735 06linuxcnc 10(15 files in 6 dirs) external axis-offset hal pins (v8) * 14http://git.linuxcnc.org/?p=linuxcnc.git;a=commitdiff;h=96a9735
[17:46:32] <skunkworks_> dgarr: cool!! andy has been asking for that!
[17:46:36] <JT-Shop2> nice
[17:46:37] <skunkworks_> well - and others
[17:46:48] <JT-Shop2> wonder if that works in real time?
[17:58:59] <skunkworks_> if it is part of motion...
[18:01:02] <JT-Shop2> I'll ask him
[18:15:42] <andypugh> What?
[18:58:41] <skunkworks_> andypugh,
http://git.linuxcnc.org/gitweb?p=linuxcnc.git;a=commitdiff;h=96a9735
[18:58:49] <skunkworks_> looks like offset pins in motion?
[19:16:00] <andypugh> That is something I had been looking for, yes.
[19:17:48] <andypugh> In fact, I was thinking about doing it myself, but hadn’t worked out where to do it. Looks like Dewey knew, though. And did the actual doing of it.
[19:18:14] <andypugh> Should be super-useful to THC with Plasma, I want it for lathe-releiving.
[21:40:38] <dgarr> seb_kuzminsky: the buildbot not currently building? maybe needs a restart
