Hi Per Glad to hear that you got it going to your satisfaction. If possible, could you write up your "journey" on the wiki so that others can follow.
Rayh On Mon, 2007-01-22 at 20:53 +0100, Per Willför wrote: > Hi all, and thanks for your input! > I've now got a functioning SMP+RTAI machine running with the following config: > - Vanilla kernel 2.6.19.2 with: > - RTAI 3.5-test1 release, and: > - EMC 2.1.0 developers something release (from CVS at linuxcnc.org) > Well, it was quite a journey to get where I'm right now, but it seems > everything is working OK by now. I have a BASE_PERIOD of 5000 ns and > the base thread is between 3000 and 3300 ns, thanks to a separate > PCI parallell I/F (thanks for the tip, Rayh!). I guess many of my > experienced problems came from the MoBo beeing too new, and thus not > fully recognized. I've done some tweaking in the BIOS settings, but > the doc's for RTAI 3.4 and upwards recommends (!) enabling some of > the previously "bad" settings. My memories, BTW, are Kingston HyperX's > and I've manually entered the recommended fast timings from the > Kingston datasheet; I would, however, be very surprised if the > base thread in RTAI was kicked out of L2 cache memory since > it is run so often... > Well, after getting the box running as I wanted to, I'm really > happy. Of course it would be better to run a stable release of > each S/W component, but in due time that will happen as well, I'm sure. > <> > <>To all you people developing EMC2 I'd just like to say thank you, > you're doing a fantastic work. I've been using EMC with a Sherline > mill since 2004 and the software is just getting better and better. > <> > <> > Best regards, > Per W > SWEDEN > > > Mario. wrote: > > Oh yes :), for low latency, you also need to set up BIOS settings > > properly, disabling and enabling a lot of things, setting PCI latency > > to 32, etc. > > > > Did you do this part? > > > > What I know/heard about 2-core RTAI support, that it is experimental, > > I did not yet hear of production version. > > > > As for low latency, I did achieve a 5.7 microsecond KLAT MAX measured > > with PIRT on a K7 processor running at maybe 2200MHz (Athlon XP > > something), it was nForce3 chipset. > > > > Also my notebook with SiS 740/650 chipset with Athlon XP (lovely > > Palomino) gets maybe 7-14 microsecond latencies at 1GHz. I don't > > remember exactly.. It was some time ago. > > > > So for low latency, you need a FAST queue, the FETCH queue, the CACHE > > queue, the CHIPSET memory and interrupt management queue. It is a lot > > more that just raw processor power. > > > > So you need adequate ratio of: > > 1) Processing power/queue size and delays > > 2) low communication and memory latency > > > > So, for Athlon AM2 you seem to use, you need to get the highest HTT > > you can - the VIA mainboard you seem to use allows for only 20% > > overclock, which works without a glitch anyway, you will want to try > > different combination of memory settings and processor > > speed/multiplier. > > > > DDR2 memory with 800"MHz" DDR2 CL4 latency would be advisable. You can > > not count on higher latency memory modules to deliver very good RTAI > > latencies ;-) > > > > Mario out. > > > > On 1/13/07, Ray Henry <[EMAIL PROTECTED]> wrote: > > > > > Hi Per > > > > > > No help on the SMP compile and run. I don't have such a mobo here. I > > > do have an Athalon64 on a N8V mobo. I do not see any big jump in > > > latency every 6 or so iterations of the test. > > > > > > I must admit when running with an 8000 base period that I was violating > > > the sentence in the troubleshooting wiki page > > > > > > http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?TroubleShooting > > > > > > "There should be no overruns, and 'lat max' should probably be > > > below your BASE_PERIOD setting." > > > > > > I did not see any overruns from the latency test but the 8000 was below > > > the 12000 lat max for that box. > > > > > > Rayh > > > > > > > > > On Sat, 2007-01-13 at 15:07 +0100, Per Willför wrote: > > > > > > > Hi! > > > > > > > > I've got some serious problems to build an SMP kernel with RTAI > > > > extensions, and I'm thinking that maybe someone else may have already > > > > achieved this. I have a system with an Athlon 64 X2 4600+ on an Asus M2V > > > > motherboard (K8T890 chipset), and I'm using Ubuntu 6.06.1 LTS with EMC2 > > > > loaded per the script on the linuxcnc.org homepage. Everything works > > > > just great in UP mode, but I'm missing the additional processor that > > > > sits there idle. My goal is to squeeze BASE_PERIOD as low as possible > > > > (to get the highest stepping freq possible, or less jitter for lower > > > > step rates), and I think an SMP kernel wold help substantially in this > > > > regard. In UP mode BASE_PERIOD can only be lowered to about 20 µs, and I > > > > would like to get down to 5-8 µs - I read a post by Ray H that he set > > > > BASE_PERIOD to 8000... When I run the RTAI test program (have forgot > > > > it's name) i get good delay numbers for 4-5 rows and then there's > > > > something that "gets in the way" every 5th - 6 th row with much longer > > > > latencies. My idea was to not optimize the interrupt handling and > > > > graphics drivers or whatever, but rather enabling the other CPU. Having > > > > tried all sorts of magma as well as vanilla kernels, it always fails > > > > when I use the combination of SMP and RTAI. > > > > > > > > For starters, I thought I could just use the magma kernel source and > > > > change one thing - enable SMP - but this wasn't the case. The machine > > > > just rebooted after i selected "magma-smp" in GRUB, if there was any > > > > error message flashing by I'm not fast enough to read it. About the same > > > > problems has occured with different vanilla kernels as well, sometimes > > > > the machine just reboots after GRUB selection, sometimes I get some > > > > output from the kernel before it freezes or crashes (BTW, is there a way > > > > to capture the console output, like "tee:ing" it to a serial port?) > > > > > > > > Please note that I haven't come as far as trying to start EMC2 on an SMP > > > > kernel; I'm still trying to boot a kernel with SMP enabled and RTAI > > > > patches. For the vanilla kernels I have been using rtai-3.4-cv and > > > > 2.6.17.6 (I started with 2.6.17.14 and went backwards unit the patch > > > > file from RTAI could be applied without errors). > > > > > > > > What am I doing wrong? > > > > > > > > Per W > > > > SWEDEN > > > > -- > > > > > > > > > > > > ------------------------------------------------------------------------- > > > > Take Surveys. Earn Cash. Influence the Future of IT > > > > Join SourceForge.net's Techsay panel and you'll get the chance to share > > > > > > > your > > > > > > > opinions on IT & business topics through brief surveys - and earn cash > > > > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > > > > _______________________________________________ > > > > Emc-users mailing list > > > > [email protected] > > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > > > > ------------------------------------------------------------------------- > > > Take Surveys. Earn Cash. Influence the Future of IT > > > Join SourceForge.net's Techsay panel and you'll get the chance to share > > > your > > > opinions on IT & business topics through brief surveys - and earn cash > > > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > > > _______________________________________________ > > > Emc-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > ------------------------------------------------------------------------- > > Take Surveys. Earn Cash. Influence the Future of IT > > Join SourceForge.net's Techsay panel and you'll get the chance to share your > > opinions on IT & business topics through brief surveys - and earn cash > > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > ____________________________________________________________________ > > > > No virus found in this incoming message. > > Checked by AVG Free Edition. > > Version: 7.5.432 / Virus Database: 268.16.10/625 - Release Date: 2007-01-13 > > 17:40 > > > > ------------------------------------------------------------------------- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to share your > opinions on IT & business topics through brief surveys - and earn cash > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > _______________________________________________ Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
