Forum Menu

ISO install of LinuxCNC on Debian 8 & Mint LMDE 2

More
10 years 8 months ago #70413 by islander261
Replied by islander261 on topic ISO install of LinuxCNC on Debian 8 & Mint LMDE 2
I have install LDME 2 64 bit OS on my Dell SFF Optiplex 745 box. Using the ISO I installed LCNC and the Preempt-RT kernel. Everything seems to work but the latency seems quite high. Please see attached image. I tried to use the tricks shown in this post www.forum.linuxcnc.org/forum/9-installin...mde-2?start=10#69182 but couldn't get the sim control to install. I am very new to using Linux and don't really know what I am doing.

Here is the results of lspci if it helps:
Code:
jd@plasma1 ~ $ lspci 00:00.0 Host bridge: Intel Corporation 82Q963/Q965 Memory Controller Hub (rev 02) 00:02.0 VGA compatible controller: Intel Corporation 82Q963/Q965 Integrated Graphics Controller (rev 02) 00:02.1 Display controller: Intel Corporation 82Q963/Q965 Integrated Graphics Controller (rev 02) 00:1a.0 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 02) 00:1a.1 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 02) 00:1a.7 USB controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 02) 00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02) 00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 02) 00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 5 (rev 02) 00:1d.0 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 02) 00:1d.1 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 02) 00:1d.2 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 02) 00:1d.7 USB controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 02) 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev f2) 00:1f.0 ISA bridge: Intel Corporation 82801HB/HR (ICH8/R) LPC Interface Controller (rev 02) 00:1f.2 IDE interface: Intel Corporation 82801H (ICH8 Family) 4 port SATA Controller [IDE mode] (rev 02) 00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 02) 00:1f.5 IDE interface: Intel Corporation 82801HR/HO/HH (ICH8R/DO/DH) 2 port SATA Controller [IDE mode] (rev 02) 02:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5754 Gigabit Ethernet PCI Express (rev 02) jd@plasma1 ~ $

I want to use this box with a Mesa 7i76E if possible, is the latency too high? Any suggestions before I start looking around for another box?

John

Please Log in or Create an account to join the conversation.

More
10 years 8 months ago - 10 years 8 months ago #70414 by tjmarch
Replied by tjmarch on topic ISO install of LinuxCNC on Debian 8 & Mint LMDE 2
You only ran latency-histogram for 24 min not long enough to tell anything. Latency plot did not look to bad. You need to invest some time and read the included documentation that was installed. The best way to learn is to do a little resurch then when you do not understand something ask. I have given you a great start with the ISO but you have to attempt to help yourself. What trouble did you have with post on lowering latency there is nothing about sim control. Did you mean something else like
SMI control.
Tim
Last edit: 10 years 8 months ago by tjmarch.

Please Log in or Create an account to join the conversation.

More
10 years 8 months ago #70416 by PCW
Replied by PCW on topic ISO install of LinuxCNC on Debian 8 & Mint LMDE 2
That latency is probably OK but note that the Broadcom Ethernet is probably not
usable for the real time Ethernet connection (Intel and Realtek are known to be OK)

Please Log in or Create an account to join the conversation.

More
10 years 8 months ago #70688 by islander261
Replied by islander261 on topic ISO install of LinuxCNC on Debian 8 & Mint LMDE 2
Hello

I have gone back and did a fair amount of testing with little improvement to show for it. I was successful in getting the SMI control software installed and run. I also experimented with using isolcpus again with little change in latency. I then installed a video card so the onboard video wasn't being used again with little change in latency.






The one think that stood out is that when using smictrl as instructed when I shut down the machine using the menu button the power does not shut off, I have to manually push the power button on the box after the black Linux Mint splash screen pops up.

I understand that I need to use an Intel or Realtek chip base NIC for real time control of a Mesa 7i76E card. Is there a preferred chip series to use or avoid?

John

Please Log in or Create an account to join the conversation.

More
10 years 8 months ago - 10 years 8 months ago #70691 by PCW
Replied by PCW on topic ISO install of LinuxCNC on Debian 8 & Mint LMDE 2
Any Intel or Realtek NIC that fits should b e OK

Isolcpus is typically a bad idea with Preempt-RT and hm2-eth (it just slows everything down)

You can probably get some improvement by using a core 2 DUO with more cache
(a E8500 has 3x the cache size of your E6400 and is about $15.00 on ebay)
Cache size makes a big difference (how much of the real time stuff stays in cache has a big effect on latency)

All this said, unless you dont meet the 1 ms thread time deadline (and so get real time errors)
the latency is pretty much immaterial

Much too much time is wasted improving latency for no real benefit, especially if you dont need software step generation
Last edit: 10 years 8 months ago by PCW.

Please Log in or Create an account to join the conversation.

More
10 years 8 months ago #70735 by jtc
Replied by jtc on topic ISO install of LinuxCNC on Debian 8 & Mint LMDE 2
Hi.


when I tried to install linuxcnc on LMDE2 using the iso, I'm only able to install the kernel. I got errors like these:
Code:
Err http://buildbot.linuxcnc.org jessie/2.7-rtpreempt Sources 403 Forbidden Err http://buildbot.linuxcnc.org jessie/2.7-rtpreempt amd64 Packages 403 Forbidden Ign http://linuxcnc.org jessie/base Translation-en Err http://buildbot.linuxcnc.org jessie/2.7-rtpreempt i386 Packages 403 Forbidden Ign http://packages.linuxmint.com betsy/import Translation-en_GB Ign http://buildbot.linuxcnc.org jessie/2.7-rtpreempt Translation-en_GB Ign http://packages.linuxmint.com betsy/import Translation-en Ign http://packages.linuxmint.com betsy/main Translation-en_GB Ign http://packages.linuxmint.com betsy/main Translation-en Ign http://packages.linuxmint.com betsy/upstream Translation-en_GB Ign http://buildbot.linuxcnc.org jessie/2.7-rtpreempt Translation-en Ign http://packages.linuxmint.com betsy/upstream Translation-en Fetched 140 kB in 16s (8,471 B/s) W: Failed to fetch http://buildbot.linuxcnc.org/dists/jessie/2.7-rtpreempt/source/Sources 403 Forbidden W: Failed to fetch http://buildbot.linuxcnc.org/dists/jessie/2.7-rtpreempt/binary-amd64/Packages 403 Forbidden W: Failed to fetch http://buildbot.linuxcnc.org/dists/jessie/2.7-rtpreempt/binary-i386/Packages 403 Forbidden E: Some index files failed to download. They have been ignored, or old ones used instead.


anyway, following the online instructions to install on debian jessie I manage to install linuxcnc.



there is any way to install linuxcnc run in place with this kernel ?

Please Log in or Create an account to join the conversation.

Time to create page: 0.097 seconds
Powered by Kunena Forum