Bas is right. Here's the referenced documentation in context. http://<http://www.machinekit.io/docs/hal/threads-and-latency/>www.machinekit.io<http://www.machinekit.io/docs/hal/threads-and-latency/>/docs/<http://www.machinekit.io/docs/hal/threads-and-latency/>hal<http://www.machinekit.io/docs/hal/threads-and-latency/>/<http://www.machinekit.io/docs/hal/threads-and-latency/>threads-<http://www.machinekit.io/docs/hal/threads-and-latency/>and-latency<http://www.machinekit.io/docs/hal/threads-and-latency/>/<http://www.machinekit.io/docs/hal/threads-and-latency/>
If you have no CPUs to spare, though, this will be of no use to you. John Morris Dovetail Automata LLC From: Bas de Bruijn Sent: Thursday, February 28, 13:43 Subject: [Machinekit] cgroups and isolating CPU’s To: [email protected] Cc: Machinekit So as not to hijack the thread, a new thread On 28 Feb 2019, at 19:20, [email protected]<mailto:[email protected]> wrote: BTW, did someone else (than Zultron) try to use the core isolation feature to "turn on" back the step signal generation in software? My electrotrash which I use for Machinekitdoes not have cores to spare. Yes, you’re probably referring to this? https<https://github.com/machinekit/machinekit/pull/1426>://<https://github.com/machinekit/machinekit/pull/1426>github.com<https://github.com/machinekit/machinekit/pull/1426>/<https://github.com/machinekit/machinekit/pull/1426>machinekit<https://github.com/machinekit/machinekit/pull/1426>/<https://github.com/machinekit/machinekit/pull/1426>machinekit<https://github.com/machinekit/machinekit/pull/1426>/pull/1426<https://github.com/machinekit/machinekit/pull/1426> Although i dont use software step generation. The latency obtained is very good (6-7 us). What was done here is to force the thread to run on designated cpu’s. Because these cpu’s were isolated during startup (isolcpus= kernel parameter) there are no other processes running on these cpu’s. These cpu’s must be the pair that share their L2 cache, or hyperthreading should be disabled and that cpu used. A setup that was historically used with iolcpus= kernel parameters was to run everything on 1 cpu (disabling all but one), so that the cpu was hogged and that got good latency results. This cgroups setup is the other way around, you’ll only run HAL on the isolated cpu’s, the /RT cpuset. I’m no expert on this so there might be some more clarification needed from the experts :) Bas -- website: http://<http://www.machinekit.io>www.machinekit.io<http://www.machinekit.io> blog: http://<http://blog.machinekit.io>blog.machinekit.io<http://blog.machinekit.io> github: https<https://github.com/machinekit>://<https://github.com/machinekit>github.com<https://github.com/machinekit>/<https://github.com/machinekit>machinekit<https://github.com/machinekit> --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to machinekit<mailto:[email protected]>[email protected]<mailto:[email protected]>. Visit this group at https<https://groups.google.com/group/machinekit>://<https://groups.google.com/group/machinekit>groups.google.com<https://groups.google.com/group/machinekit>/group/<https://groups.google.com/group/machinekit>machinekit<https://groups.google.com/group/machinekit>. For more options, visit https<https://groups.google.com/d/optout>://<https://groups.google.com/d/optout>groups.google.com<https://groups.google.com/d/optout>/d/<https://groups.google.com/d/optout>optout<https://groups.google.com/d/optout>. -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. Visit this group at https://groups.google.com/group/machinekit. For more options, visit https://groups.google.com/d/optout.
