On Wednesday 12 December 2012 18:22:00 Sven Wesley did opine: > 2012/12/12 Gene Heskett <ghesk...@wdtv.com> > > > I will say it. If its a 64 bit install, then it is not the rtai > > patched kernel, and the results predictably will be poorer. > > Read my post again. There are two different PC's involved in my tests. > One is now installed with 64 bit Ubuntu - not LinuxCNC. The other one > is installed with LinuxCNC. > Ahh, sorry, I missed that detail. My apologies.
> > Neither of my machines has ever exceeded 8u-s, with only one stick of > > memory in them, 2Gb IOW. Latencyplot has been running on the lathes > > machine for about an hour, base-thread peak is 5 u-s, servo-thread > > peak is 5 u-s. > > Well, good for you and I would be glad to share that experience. But the > fact remains, I have two D5252MW's and none of them have been close to > your levels. Did you push the hardware? Did you start a download, a > browser, glxgears? if I let it idle of course it will look good. That > is not realistic though and as I have stated earlier it's enough to > start a Firefox to totally destroy the figures. Looks a lot better now > when both memory banks are used, still double up from your latency. > I wonder if this board has changed too much over releases, maybe we > don't have the same hardware if we dig into the board itself. Now that I wouldn't doubt for more than 50 milliseconds. I bought these two about 6 months apart, and brought both of them up to the latest bios (that is important), but the newest one, running my lathe, does good to get a 2 week uptime, it can go away, and has many times, doing a self reboot. The screen goes dark without warning & the next thing I see 7 or 8 secs later in the bios signing on. I can't remember the last time I rebooted the earlier one running the mill. > > > I don't think you changed the graphics driver just by lowering the > > > latency. I have not done much Linux stuff in years, but I'm > > > wondering what X graphics driver you are using? Can you force the > > > graphics driver into some VGA totally software render mode? > > > The linux/intel driver that Ubuntu auto-installs, and that part seems to be bullet-proof, running in 1680x1050 32 bit mode. On both machines. > > > Also remote into it, and run it as a headless station. I should do > > > this and see how it performs. Maybe next time I > > > > > > One thing though, I filled one of the boards with 8 GB RAM (2x4). > > > > That board is running 64 bit Ubuntu in the office and it happily > > > > reported 8 GB even though the hardware spec says max 4 GB. It > > > > seems that 4 GB is a soft limit. > > > > > > Running a 32 bit kernel? I don't think you'll be able to address > > > over 4g via sw. Maybe they expect people to run windows, not > > > Linux! > > > > > > Interesting that you can put the RAM in, as like you, I had assumed > > > that it was not just a SW limit. I'd put another 2Gb stick in each of mine, just on general principles, but I'd have to net order it, staples sent them out for 5 micron gold flash & doubled the newegg price. > > > Thanks; > > > > > > John A. Stewart. > > > > A 64 bit linux that has a problem with even 64Gb of ram should have a > > bug report filed. 32 bit however has to jump through some time > > consuming hoops. > > I wrote soft limit. Not software limit. The board specification says max > 4 GB RAM and it can be rewritten into "is only guaranteed to work with > 4 GB, but can handle more on your own risk". The board itself is a 64 > bit architecture. The software limit theoretically for a 64 bit system > is 2^64 bytes (16 exabytes). I have a bunch of blade servers at the > office with 300+ GB RAM. > I did the remote test earlier (also reported to this list) and the > figures are better. Have in mind that half of this list will stupidify > you if you suggest running two PC's at the same time. > The graphics driver of this board share memory with the OS, when going > down in resolution it will affect the memory usage. The desktop also > becomes a bit more responsive but looks like crap in the lower res when > the same monitor is used. Nevertheless it was no real performance > impact. I can watch HD video on my cell phone but not on these PC's. > Probably they will be used as automation controllers, end up in a CNC > cabinet will not happen. > > Regards, > Sven > ------------------------------------------------------------------------ > ------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free > Trial Remotely access PCs and mobile devices and provide instant > support Improve your efficiency, and focus on delivering more value-add > services Discover what IT Professionals Know. Rescue delivers > http://p.sf.net/sfu/logmein_12329d2d > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> is up! The world really isn't any worse. It's just that the news coverage is so much better. I was taught to respect my elders, but its getting harder and harder to find any... ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
