On Tuesday, January 03, 2012 02:41:08 PM Kent A. Reed did opine: > On 1/2/2012 11:24 PM, Kent A. Reed wrote: > > On 1/2/2012 10:35 PM, Jon Elson wrote: > >> gene heskett wrote: > >>> Is anyone running emc on this? How is the latency? > >> > >> I've tested the Intel D525MW motherboard, and put it in the database. > >> The servo thread jitter was 15595, the base thread was 11921. > >> That is fine for any system with a hardware interface (servo or > >> stepper) but may be a little marginal for software step generation. > >> Since I'm a servo bigot, it was quite good for me. The on-board > >> parallel port passed all the tests with my EPP devices. EMC 2.4.x > >> with Ubuntu 10.04 loads and runs with no quirks at all. I did the > >> install on a 16 GB SSD "hard" drive. > >> > >> Jon > > > > Jon: > > > > This is a multi-cpu board. Did you set the isolcpus boot parameter? > > > > The reason I ask is IIRC I got similar numbers with a standard boot > > from the LiveCD on my ASUS board and saw them drop below 10000 when I > > set isolcpus=1. > > > > This may be a false memory (I did the tests last winter) and I'm away > > from the board at the moment. I'll do the tests again in the morning > > and this time I'll post the results on the Wiki. > > > > Regards, > > Kent > > Jon (and Gene if he gets a motherboard outfitted with an Intel Atom > cpu): > On order A/O 15 minutes ago. But this didn't get sent, snow needed shoveling, so further update since.
I put the better PSU in, but had problems getting a clean boot, and once I did get one, uptime was in minutes, 2 more times. Going to my IR thermometer because gkrellm said the hard drive was pretty warm, I noted that all the caps in the cpu supply on the mobo had tops all swelled up. All 6 of them. Duh, perfect explanation, everything fits. They can be replaced as Dave keeps a grocery sack of those at the tv station, all I have to do is get it there, or just go get some since I have the tools to replace them myself. But with the D525 already coming, it can wait till I need another box for the lathe. I did develop some interesting data vis-a-vis the usb mouse and keyboard. Yes, they hurt latency, as much as 15 u-secs worth. Unforch, my junk box did not disgorge any ps2 mice to facilitate a test for those. So it will be interesting to repeat those tests with the new box when it gets here. > To follow up on this, I just ran 15-minute latency tests on my ASUS > AT5NM10-I board first with a stock boot and then with isolcpus=1 as a > boot parameter. I've posted my results in the table on the Wiki. > > In brief, isolating one cpu shaved approximately 6000ns off the max > jitters reported for both the base thread and the servo thread. > > Of course the latency test should be run much longer but I believe these > numbers are indicative. YMMV > > Regards, > Kent > > > ------------------------------------------------------------------------ > ------ Write once. Port to many. > Get the SDK and tools to simplify cross-platform app development. Create > new or port existing apps to sell to consumers worldwide. Explore the > Intel AppUpSM program developer opportunity. appdeveloper.intel.com/join > http://p.sf.net/sfu/intel-appdev > _______________________________________________ > 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> Although the moon is smaller than the earth, it is farther away. ------------------------------------------------------------------------------ Ridiculously easy VDI. With Citrix VDI-in-a-Box, you don't need a complex infrastructure or vast IT resources to deliver seamless, secure access to virtual desktops. With this all-in-one solution, easily deploy virtual desktops for less than the cost of PCs and save 60% on VDI infrastructure costs. Try it free! http://p.sf.net/sfu/Citrix-VDIinabox _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
