Hi everyone,
First time poster here. I wanted my first post to resemble a contribution because I know I'll be asking for help from y'all in the near future. Here's the results of a 2 hour test on my recently acquired Dell Optiplex 7010 SFF (SSD, 8GB RAM, onboard graphics) using Debian Buster 10.7 with RTAI kernel. BIOS modifications are:
- Using only one core
- Disabled SpeedStep
- Disabled C States Control
- Blocked sleep
- Disabled all virtualization support options
I also tried disabling fan control, TurboBoost, USB wake, and audio individually without much performance gain so they were re-enabled. If anyone else is considering using the Dell 7010, I'd suggest starting with Debian as I was getting over 1000us servo thread latency without even using this test script on Mint 20.1 with PREEMPT_RT kernel. Debian with PREEMPT_RT dropped that to around 65us running this test script for 2 hours. Finally, switching to RTAI dropped the latency to around 20us as shown here.
Thanks to my1987toyota for describing their similar experience in
this thread,
as I may have given up on the 7010 without reading about his switch to Debian.
Since I'm trying to keep costs down, I'm hoping to try parallel port software stepping on a basic 3-axis small vertical mill closed loop stepper setup (still deciding on which mill). I'm hoping someone here can tell me if this latency should be sufficient or if I should consider a FPGA board setup instead. Ultra fast feedrates aren't a requirement for my uses, mainly prototyping small parts with softer materials.
Thanks to everyone on this forum for all the useful info and I can't wait till I'm finally making chips!
- Mark
Code:
LinuxCNC pc tests, version 20200930, started 02.02.2021 09:37:00
********************************************************************************
General info:
Dell Inc., OptiPlex 7010
Bios version A29, dated 06/28/2018
Chipset: Intel Corporation 7 Series/C216
Harddisk is non-rotational, ie. SSD
The amount of swap currently used is 0
================================================================================
CPU related data:
model name : Intel(R) Core(TM) i5-3470 CPU @ 3.20GHz
cpu cores : 1
stepping : 9
cache size : 6144 KB
================================================================================
RAM related data:
Maximum Capacity: 32 GB
Size: No Module Installed
Size: 4096 MB
Size: No Module Installed
Size: 4096 MB
================================================================================
GPU related data:
product: Xeon E3-1200 v2/3rd Gen Core processor 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 : gnome
Windowmanager : Metacity (Marco)
Displaymanager : lightdm
================================================================================
Kernel related data:
Kernel 4.14.174-rtai-amd64
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash resume=UUID=c1b3a866-389a-48fa-8427-972a3ab4953d"
Cpu idle driver: ================================================================================
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 : PixArt Dell MS116 USB Optical Mouse
Mice attached to USB:
Keyboards attached to USB:
================================================================================
LinuxCNC related data:
LinuxCNC version is:
================================================================================
Preparing for latency test:
Started glxgears No. 1, 2, 3, 4, 5
..........
Started firefox with 'https://vimeo.com/150574260', WID 58720259
================================================================================
Command for latency test is:
su cnc -c "latency-histogram --nobase --sbinsize 1000 --nox 2>&1 | tee -a 1612283819.lat &"
Latency testing loop started Tue 02 Feb 2021 09:37:14 AM MST,
should end after Tue 02 Feb 2021 11:37:14 AM MST
================================================================================
Swap useage: prerun: 0, running: 0
================================================================================
CPU core temperatures:
Core 0: Tmin: 40.0°C, Tmax: 53.0°C, (high = +85.0°C, crit = +105.0°C)
================================================================================
last latency data is as follows:.
7204 secs servo min: -18.600 uS max: 20.200 uS sdev: 2.000 uS
7205 secs servo min: -18.600 uS max: 20.200 uS sdev: 2.000 uS
Topic Author
