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):
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
