Results of latency test, list of computers tested for use with LinuxCNC

More
5 years 4 months ago #211401 by degreaser
Optiplex 980MT. At this point I'm chasing nanoseconds. This used a non-standard kernel, specifically the rt kernel from xanmod.org/ . The standard kernels are giving good but not quite as good results so far.

Also, I applied the irq remapping to cpu0 per this post: forum.linuxcnc.org/18-computer/25927-red...lticore-pc-s-success

That change cut the latencies in half.


Code:
LinuxCNC pc tests, version 20200930, started 06.06.2021 16:56:40 ******************************************************************************** General info: Dell Inc., OptiPlex 980 Bios version A18, dated 02/27/2018 Chipset: Intel Corporation 5 Series/3400 Series Harddisk is non-rotational, ie. SSD The amount of swap currently used is 0 ================================================================================ CPU related data: model name : Intel(R) Core(TM) i5 CPU 650 @ 3.20GHz cpu cores : 2 stepping : 5 cache size : 4096 KB ================================================================================ RAM related data: Maximum Capacity: 16 GB Size: 4096 MB Size: 4096 MB Size: No Module Installed Size: No Module Installed ================================================================================ GPU related data: product: Core Processor Integrated Graphics Controller configuration: driver=i915 latency=0 ================================================================================ Parallel port related data: number of parallel ports is 1 parport0: PC-style at 0x378 (0x778), irq 7, using FIFO [PCSPP,TRISTATE,COMPAT,EPP,ECP] ================================================================================ Os and desktop related data: PRETTY_NAME="Debian GNU/Linux 10 (buster)" Should the info below not match with your machine, kindly post the output of pstree here, including a brief desciption of your desktop environment, window manager and display manager. Tia https://forum.linuxcnc.org/18-computer/39370-script-for-automated-testing-of-computer-l atency Desktop environment : Windowmanager : e16 Displaymanager : lightdm ================================================================================ Kernel related data: Kernel 5.10.41-rt42-xanmod1 GRUB_CMDLINE_LINUX_DEFAULT="quiet isolcpus=1 mitigations=off intel_idle.max_cstate=0 pr ocessor.max_cstate=0 idle=poll acpi_irq_nobalance noirqbalance" Cpu idle driver: none ================================================================================ Kernel modules data: Check if pcspkr is loaded: Yes, may cause bigger latency. can be eliminated using: sudo echo "install pcspkr /bin/true" >/etc/modprobe.d/pcspkr.conf Check if snd modules are loaded: Yes, may cause bigger latency. can probably be disabled in bios, alternatively, you can run "./block-snd-modules" which has just now been created for your convenience. ================================================================================ Keyboard & Mouse related data: Number of mice: 3 Mouse 0 : Logitech USB Optical Mouse Mouse 1 : CHESEN PS2 to USB Converter Mouse Mouse 2 : CHESEN PS2 to USB Converter Mouse Mice attached to USB: Logitech, Inc. M105 Optical Mouse Chesen Electronics Corp. PS/2 Keyboard+Mouse Adapter Keyboards attached to USB: Chesen Electronics Corp. PS/2 Keyboard+Mouse Adapter ================================================================================ LinuxCNC related data: LinuxCNC version is: 2.8.1 ================================================================================ Preparing for latency test: Started glxgears No. 1, 2, 3, 4, 5 .......... Started firefox with 'https://vimeo.com/150574260', WID 14680112 ================================================================================ Command for latency test is: su cadusr -c "latency-histogram --bbinsize 1000 --base 100000 --sbinsize 1000 --nox 2> &1 | tee -a 1623023787.lat &" Latency testing loop started Sun 06 Jun 2021 04:56:54 PM PDT, should end after Sun 06 Jun 2021 06:56:54 PM PDT ================================================================================ Swap useage: prerun: 0, running: 0 ================================================================================ CPU core temperatures: Core 0: Tmin: 37.0°C, Tmax: 41.0°C, (high = +89.0°C, crit = +105.0°C) Core 2: Tmin: 39.0°C, Tmax: 42.0°C, (high = +89.0°C, crit = +105.0°C) ================================================================================ last latency data is as follows:. 7202 secs base min: -9.400 uS max: 9.300 uS sdev: 0.300 uS 7202 secs servo min: -6.900 uS max: 6.900 uS sdev: 0.400 uS

Please Log in to join the conversation.

More
5 years 4 months ago #212460 by JackW327
All I've done so far is disable the front panel USB ports. I shall disable the sound and see where that takes us ... I have a Mesa 7i95 BTW, so, I'm not too worried. Would like to get it a bit lower.

Code:
LinuxCNC pc tests, version 20200930, started 20.06.2021 02:30:43 ******************************************************************************** General info: Dell Inc., OptiPlex 790 Bios version A11, dated 12/30/2011 Chipset: Intel Corporation 6 Series/C200 Series Harddisk is non-rotational, ie. SSD The amount of swap currently used is 0 ================================================================================ CPU related data: model name : Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz cpu cores : 4 stepping : 7 cache size : 6144 KB ================================================================================ RAM related data: Maximum Capacity: 32 GB Size: 4096 MB Size: 4096 MB Size: 4096 MB Size: 4096 MB ================================================================================ GPU related data: product: 2nd Generation Core Processor Family Integrated Graphics Controller configuration: driver=i915 latency=0 ================================================================================ Parallel port related data: number of parallel ports is 0 ================================================================================ Os and desktop related data: PRETTY_NAME="Debian GNU/Linux 10 (buster)" Should the info below not match with your machine, kindly post the output of pstree here, including a brief desciption of your desktop environment, window manager and display manager. Tia https://forum.linuxcnc.org/18-computer/39370-script-for-automated-testing-of-computer-latency Desktop environment : xfce4 Windowmanager : Xfwm4 Displaymanager : lightdm ================================================================================ Kernel related data: Kernel 4.19.0-11-rt-amd64 Cpu idle driver: intel_idle ================================================================================ Kernel modules data: Check if pcspkr is loaded: Yes, may cause bigger latency. can be eliminated using: sudo echo "install pcspkr /bin/true" >/etc/modprobe.d/pcspkr.conf Check if snd modules are loaded: Yes, may cause bigger latency. can probably be disabled in bios, alternatively, you can run "./block-snd-modules" which has just now been created for your convenience. ================================================================================ Keyboard & Mouse related data: Number of mice: 1 Mouse 0 : Logitech M705 Mice attached to USB: Keyboards attached to USB: ================================================================================ LinuxCNC related data: LinuxCNC version is: 2.8.1 ================================================================================ Preparing for latency test: Started glxgears No. 1, 2, 3, 4, 5 .......... Started firefox with 'https://vimeo.com/150574260', WID 33554794 ================================================================================ Command for latency test is: su user -c "latency-histogram --nobase --sbinsize 1000 --nox 2>&1 | tee -a 1624156216.lat &" Latency testing loop started Sun 20 Jun 2021 02:30:58 AM UTC, should end after Sun 20 Jun 2021 04:30:58 AM UTC ================================================================================ Swap useage: prerun: 0, running: 0 ================================================================================ CPU core temperatures: Core 0: Tmin: 35.0°C, Tmax: 70.0°C, (high = +80.0°C, crit = +99.0°C) Core 1: Tmin: 37.0°C, Tmax: 73.0°C, (high = +80.0°C, crit = +99.0°C) Core 2: Tmin: 35.0°C, Tmax: 71.0°C, (high = +80.0°C, crit = +99.0°C) Core 3: Tmin: 34.0°C, Tmax: 71.0°C, (high = +80.0°C, crit = +99.0°C) ================================================================================ last latency data is as follows:. 7204 secs servo min: -71.000 uS max: 83.600 uS sdev: 3.400 uS 7205 secs servo min: -71.000 uS max: 83.600 uS sdev: 3.400 uS

Please Log in to join the conversation.

  • BeagleBrainz
  • New Member
  • New Member
More
5 years 4 months ago #212502 by BeagleBrainz

degreaser wrote: Optiplex 980MT. At this point I'm chasing nanoseconds. This used a non-standard kernel, specifically the rt kernel from xanmod.org/ . The standard kernels are giving good but not quite as good results so far.

Also, I applied the irq remapping to cpu0 per this post: forum.linuxcnc.org/18-computer/25927-red...lticore-pc-s-success

That change cut the latencies in half.


Code:
LinuxCNC pc tests, version 20200930, started 06.06.2021 16:56:40 ******************************************************************************** General info: Dell Inc., OptiPlex 980 Bios version A18, dated 02/27/2018 Chipset: Intel Corporation 5 Series/3400 Series Harddisk is non-rotational, ie. SSD The amount of swap currently used is 0 ================================================================================ CPU related data: model name : Intel(R) Core(TM) i5 CPU 650 @ 3.20GHz cpu cores : 2 stepping : 5 cache size : 4096 KB ================================================================================ RAM related data: Maximum Capacity: 16 GB Size: 4096 MB Size: 4096 MB Size: No Module Installed Size: No Module Installed ================================================================================ GPU related data: product: Core Processor Integrated Graphics Controller configuration: driver=i915 latency=0 ================================================================================ Parallel port related data: number of parallel ports is 1 parport0: PC-style at 0x378 (0x778), irq 7, using FIFO [PCSPP,TRISTATE,COMPAT,EPP,ECP] ================================================================================ Os and desktop related data: PRETTY_NAME="Debian GNU/Linux 10 (buster)" Should the info below not match with your machine, kindly post the output of pstree here, including a brief desciption of your desktop environment, window manager and display manager. Tia https://forum.linuxcnc.org/18-computer/39370-script-for-automated-testing-of-computer-l atency Desktop environment : Windowmanager : e16 Displaymanager : lightdm ================================================================================ Kernel related data: Kernel 5.10.41-rt42-xanmod1 GRUB_CMDLINE_LINUX_DEFAULT="quiet isolcpus=1 mitigations=off intel_idle.max_cstate=0 pr ocessor.max_cstate=0 idle=poll acpi_irq_nobalance noirqbalance" Cpu idle driver: none ================================================================================ Kernel modules data: Check if pcspkr is loaded: Yes, may cause bigger latency. can be eliminated using: sudo echo "install pcspkr /bin/true" >/etc/modprobe.d/pcspkr.conf Check if snd modules are loaded: Yes, may cause bigger latency. can probably be disabled in bios, alternatively, you can run "./block-snd-modules" which has just now been created for your convenience. ================================================================================ Keyboard & Mouse related data: Number of mice: 3 Mouse 0 : Logitech USB Optical Mouse Mouse 1 : CHESEN PS2 to USB Converter Mouse Mouse 2 : CHESEN PS2 to USB Converter Mouse Mice attached to USB: Logitech, Inc. M105 Optical Mouse Chesen Electronics Corp. PS/2 Keyboard+Mouse Adapter Keyboards attached to USB: Chesen Electronics Corp. PS/2 Keyboard+Mouse Adapter ================================================================================ LinuxCNC related data: LinuxCNC version is: 2.8.1 ================================================================================ Preparing for latency test: Started glxgears No. 1, 2, 3, 4, 5 .......... Started firefox with 'https://vimeo.com/150574260', WID 14680112 ================================================================================ Command for latency test is: su cadusr -c "latency-histogram --bbinsize 1000 --base 100000 --sbinsize 1000 --nox 2> &1 | tee -a 1623023787.lat &" Latency testing loop started Sun 06 Jun 2021 04:56:54 PM PDT, should end after Sun 06 Jun 2021 06:56:54 PM PDT ================================================================================ Swap useage: prerun: 0, running: 0 ================================================================================ CPU core temperatures: Core 0: Tmin: 37.0°C, Tmax: 41.0°C, (high = +89.0°C, crit = +105.0°C) Core 2: Tmin: 39.0°C, Tmax: 42.0°C, (high = +89.0°C, crit = +105.0°C) ================================================================================ last latency data is as follows:. 7202 secs base min: -9.400 uS max: 9.300 uS sdev: 0.300 uS 7202 secs servo min: -6.900 uS max: 6.900 uS sdev: 0.400 uS


Unless you are after something high speed, and there are better options, I’d stop. For software stepping you have really good numbers. Chasing down nanoseconds isn’t going to get you anything in practical terms.
What would be a great idea is to start your own thread regarding installing the kernel and the changes you made to get those figures. Make mention of your OS and things like that.
Like I said you have some really good numbers there.

In saying all that, I think if you use the noatime option in fstab, it’s the option that doesn’t record when a file was accessed, you might get a slight gain. You might have to check if that is the correct form.
Whilst I haven’t looked into it, reducing the amount of logging could do something. That’s if you feel keen and adventurous.
If you have PS/2 ports available for kb & mouse sometimes the use of them rather than USB can knock a bit off. Tho this might not be an option.
At the end of the day I’d trade stability for the sake of a few 1000ns.

Please Log in to join the conversation.

More
5 years 4 months ago #212525 by JackW327
So this is interesting ... I decided to re-enable the front USB ports as the difference wasn't that much, and I removed the sound moduled. '# lsmod | grep snd' returns nothing at this point whereas it did before.

Also I got my PCIe 1x WiFi NIC (Atheros AR9580 chipset) & installed that.

Net is a slight increase in latency.

With the new NIC I can now disable two of the USB banks. I'll do that, test again, and report back.
Code:
LinuxCNC pc tests, version 20200930, started 20.06.2021 14:04:37 ******************************************************************************** General info: Dell Inc., OptiPlex 790 Bios version A11, dated 12/30/2011 Chipset: Intel Corporation 6 Series/C200 Series Harddisk is non-rotational, ie. SSD The amount of swap currently used is 0 ================================================================================ CPU related data: model name : Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz cpu cores : 4 stepping : 7 cache size : 6144 KB ================================================================================ RAM related data: Maximum Capacity: 32 GB Size: 4096 MB Size: 4096 MB Size: 4096 MB Size: 4096 MB ================================================================================ GPU related data: product: 2nd Generation Core Processor Family Integrated Graphics Controller configuration: driver=i915 latency=0 ================================================================================ Parallel port related data: number of parallel ports is 0 ================================================================================ Os and desktop related data: PRETTY_NAME="Debian GNU/Linux 10 (buster)" Should the info below not match with your machine, kindly post the output of pstree here, including a brief desciption of your desktop environment, window manager and display manager. Tia https://forum.linuxcnc.org/18-computer/39370-script-for-automated-testing-of-computer-latency Desktop environment : xfce4 Windowmanager : Xfwm4 Displaymanager : lightdm ================================================================================ Kernel related data: Kernel 4.19.0-11-rt-amd64 GRUB_CMDLINE_LINUX_DEFAULT="quiet" Cpu idle driver: intel_idle ================================================================================ Kernel modules data: Check if pcspkr is loaded: Yes, may cause bigger latency. can be eliminated using: sudo echo "install pcspkr /bin/true" >/etc/modprobe.d/pcspkr.conf Check if snd modules are loaded: No, which is good! ================================================================================ Keyboard & Mouse related data: Number of mice: 1 Mouse 0 : Logitech M705 Mice attached to USB: Keyboards attached to USB: ================================================================================ LinuxCNC related data: LinuxCNC version is: 2.8.1 ================================================================================ Preparing for latency test: Started glxgears No. 1, 2, 3, 4, 5 .......... Started firefox with 'https://vimeo.com/150574260', WID 60817411 ================================================================================ Latency testing loop started Sun 20 Jun 2021 02:04:52 PM PDT, should end after Sun 20 Jun 2021 04:04:52 PM PDT Command for latency test is: su jdelaney -c "latency-histogram --nobase --sbinsize 1000 --nox 2>&1 | tee -a 1624223073.lat &" ================================================================================ Swap useage: prerun: 0, running: 0 ================================================================================ CPU core temperatures: Core 0: Tmin: 40.0°C, Tmax: 70.0°C, (high = +80.0°C, crit = +99.0°C) Core 1: Tmin: 43.0°C, Tmax: 73.0°C, (high = +80.0°C, crit = +99.0°C) Core 2: Tmin: 41.0°C, Tmax: 71.0°C, (high = +80.0°C, crit = +99.0°C) Core 3: Tmin: 40.0°C, Tmax: 70.0°C, (high = +80.0°C, crit = +99.0°C) ================================================================================ last latency data is as follows:. 7202 secs servo min: -71.500 uS max: 87.100 uS sdev: 3.200 uS 7203 secs servo min: -71.500 uS max: 87.100 uS sdev: 3.200 uS

Please Log in to join the conversation.

More
5 years 4 months ago #212534 by JackW327
Better ... The one quad USB bank is the only one enabled. PCI slot disabled. Switched to the display port adapter from the VGA port. And I see I did not get the PC speaker unloaded. Okay, one more time ...
Code:
LinuxCNC pc tests, version 20200930, started 20.06.2021 17:02:00 ******************************************************************************** General info: Dell Inc., OptiPlex 790 Bios version A11, dated 12/30/2011 Chipset: Intel Corporation 6 Series/C200 Series Harddisk is non-rotational, ie. SSD The amount of swap currently used is 0 ================================================================================ CPU related data: model name : Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz cpu cores : 4 stepping : 7 cache size : 6144 KB ================================================================================ RAM related data: Maximum Capacity: 32 GB Size: 4096 MB Size: 4096 MB Size: 4096 MB Size: 4096 MB ================================================================================ GPU related data: product: 2nd Generation Core Processor Family Integrated Graphics Controller configuration: driver=i915 latency=0 ================================================================================ Parallel port related data: number of parallel ports is 0 ================================================================================ Os and desktop related data: PRETTY_NAME="Debian GNU/Linux 10 (buster)" Should the info below not match with your machine, kindly post the output of pstree here, including a brief desciption of your desktop environment, window manager and display manager. Tia https://forum.linuxcnc.org/18-computer/39370-script-for-automated-testing-of-computer-latency Desktop environment : xfce4 Windowmanager : Xfwm4 Displaymanager : lightdm ================================================================================ Kernel related data: Kernel 4.19.0-11-rt-amd64 GRUB_CMDLINE_LINUX_DEFAULT="quiet" Cpu idle driver: intel_idle ================================================================================ Kernel modules data: Check if pcspkr is loaded: Yes, may cause bigger latency. can be eliminated using: sudo echo "install pcspkr /bin/true" >/etc/modprobe.d/pcspkr.conf Check if snd modules are loaded: No, which is good! ================================================================================ Keyboard & Mouse related data: Number of mice: 1 Mouse 0 : Logitech M705 Mice attached to USB: Keyboards attached to USB: ================================================================================ LinuxCNC related data: LinuxCNC version is: 2.8.1 ================================================================================ Preparing for latency test: Started glxgears No. 1, 2, 3, 4, 5 .......... Started firefox with 'https://vimeo.com/150574260', WID 50331651 ================================================================================ Command for latency test is: su jdelaney -c "latency-histogram --nobase --sbinsize 1000 --nox 2>&1 | tee -a 1624233718.lat &" Latency testing loop started Sun 20 Jun 2021 05:02:14 PM PDT, should end after Sun 20 Jun 2021 07:02:14 PM PDT ================================================================================ Swap useage: prerun: 0, running: 0 ================================================================================ CPU core temperatures: Core 0: Tmin: 41.0°C, Tmax: 70.0°C, (high = +80.0°C, crit = +99.0°C) Core 1: Tmin: 43.0°C, Tmax: 73.0°C, (high = +80.0°C, crit = +99.0°C) Core 2: Tmin: 43.0°C, Tmax: 71.0°C, (high = +80.0°C, crit = +99.0°C) Core 3: Tmin: 40.0°C, Tmax: 70.0°C, (high = +80.0°C, crit = +99.0°C) ================================================================================ last latency data is as follows:. 7203 secs servo min: -75.600 uS max: 77.700 uS sdev: 4.500 uS 7204 secs servo min: -75.600 uS max: 77.700 uS sdev: 4.500 uS

Please Log in to join the conversation.

More
5 years 4 months ago #212578 by JackW327
Edit - Well ... not too swift here ... my BIOS is horribly out of date as are some other things. I need to update all that and get back to ya'll. Sorry!

Thanks
-jd

Please Log in to join the conversation.

More
5 years 3 weeks ago #222359 by radom
I wanted to use some small form factor pc for my next retrofit so I got used Fujitsu S720 for cheap,
there is not much in bios, I disabled audio and that's it

result is:
Code:
[code]1204 secs  servo min:-178.400 uS max: 214.400 uS sdev:  13.700 uS

is there anything I can try to make it work with 7i92+7i77 cards?
also, script hangs when trying to read cpu temperature
Code:
[code]LinuxCNC pc tests, version 20200930, started 06.10.2021 14:41:41 ******************************************************************************** General info: FUJITSU,  FUTRO S720 Bios version V4.6.5.4 R1.15.0 for D3313-B1x, dated 11/06/2014 Chipset: Harddisk is non-rotational, ie. SSD The amount of swap currently used is 0 ================================================================================ CPU related data: model name    : AMD GX-217GA SOC with Radeon(tm) HD Graphics cpu cores    : 2 stepping    : 1 cache size    : 1024 KB ================================================================================ RAM related data: Maximum Capacity: 4 GB Maximum Voltage: 1.5 V Size: 4096 MB ================================================================================ GPU related data: product: Kabini [Radeon HD 8280E] configuration: driver=radeon latency=0 ================================================================================ Parallel port related data: number of parallel ports is 0 ================================================================================ Os and desktop related data: PRETTY_NAME="Debian GNU/Linux 10 (buster)" Should the info below not match with your machine, kindly post the output of pstree here, including a brief desciption of your desktop environment, window manager and display manager. Tia https://forum.linuxcnc.org/18-computer/39370-script-for-automated-testing-of-computer-latency Desktop environment : gnome Windowmanager       : Xfwm4 Displaymanager      : lightdm ================================================================================ Kernel related data: Kernel 4.19.0-17-rt-amd64 GRUB_CMDLINE_LINUX_DEFAULT="quiet" Cpu idle driver: acpi_idle ================================================================================ Kernel modules data: Check if pcspkr is loaded: No, which is good! Check if snd modules are loaded: No, which is good! ================================================================================ Keyboard & Mouse related data: Number of mice: 1 Mouse 0 : Logitech M570 Mice  attached to USB: Keyboards attached to USB: ================================================================================ LinuxCNC related data: LinuxCNC version is: 2.8.2.11.g6a3d0a434 ================================================================================ Preparing for latency test: Started glxgears No. 1, 2, 3, 4, 5 .......... Started firefox with 'https://vimeo.com/150574260', WID 33554584 ================================================================================ Command for latency test is: su radom -c  "latency-histogram --nobase  --sbinsize 1000 --nox 2>&1 | tee -a without-wifi.lat &" Latency testing loop started Wed 06 Oct 2021 02:41:58 PM CEST, should end after Wed 06 Oct 2021 03:01:58 PM CEST ================================================================================ Swap useage: prerun: 0, running: 0 ================================================================================ CPU core temperatures:
 
Code:
fam15h_power-pci-00c4 Adapter: PCI adapter power1:           N/A  (crit =  15.00 W) radeon-pci-0008 Adapter: PCI adapter temp1:        +43.0°C  (crit = +120.0°C, hyst = +90.0°C) k10temp-pci-00c3 Adapter: PCI adapter temp1:        +43.5°C  (high = +70.0°C)                        (crit = +100.0°C, hyst = +99.0°C)
[/code][/code]
 

Please Log in to join the conversation.

More
5 years 3 weeks ago #222368 by tommylight
Connect the Mesa card and test, should work still.

Please Log in to join the conversation.

More
5 years 3 weeks ago #222436 by radom

Connect the Mesa card and test, should work still.
 

I'm getting unexpected realtime delay on task 0 with period 1000000 and some other errors

Please Log in to join the conversation.

More
5 years 3 weeks ago #222443 by tommylight
Not good, probably also cutting the link to the Mesa board, right?

Please Log in to join the conversation.

Time to create page: 0.463 seconds
Powered by Kunena Forum