<continuing our dialog about the latency spikes bjørn is observing with his Intel D525MW MB>
On 3/28/2013 5:23 AM, bjørn wrote: > that I bought the power supply together with the D525MW board. here are a > link - > http://www.ebay.com/itm/160721043666?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649 > it says 60w but i don't know the quality of it. I will test another one > when i get it in a week. Actually the "80" in its model number signifies 80w rating. It's a lightweight power supply but its specifications (http://www.logicsupply.com/products/picopsu_80?gclid=CNjTooGsn7YCFdGd4Aod6lIA-g) suggests it is adequate for the D525MW itself (see table 30, http://downloadmirror.intel.com/19123/eng/D525MW_D525MWV_TechProdSpec.pdf). I don't know how much additional load you have with your SSD drive, etc. I don't know how well these little guys filter spikes on the power mains but that can be tested by powering it from an UPS or power conditioner. (This is just good housekeeping. I haven't had problems with powerline noise in my home but it was a problem in my lab at work. It can come from unexpected sources. Years ago, a new copier machine in a nearby office generated enough EMI/RFI to drive my experimental apparatus crazy.) These PicoPSUs don't have much thermal mass. You probably should make sure it is staying cool. > > I to have seen the problem regarding USB and latency on my mill and > plasma table. I told the guys in the shop to transfer files from USB > thumbdrive to desktop and remove USB thumbdrive > before running Linuxcnc > > at first i started out with a wireless mouse and keypad with a USB > dongle, but replaced it with USB when the spikes appeared. i have now > tested using a ps2 mouse, i do not have a ps2 keyboard so that's still > USB. but i have tried to disconnect and connect it while the > latency-test where running and no spikes i left it out and no other USB > devices connected, let the test run for 5-6 hours but still spikes at > 50000 - 60000. I'd say you've exercised due diligence:-) I keep mulling over this "5-6 hours" observation. I know we recommend running the latency test for a long time but I don't think we understand why these spiking events show up rarely. It's all well and good to blame power saving features in modern CPUs but they are functioning over much smaller time scales. If they are involved in 5-6 hour spikes, then it would seem we're experiencing some sort of "perfect storm" phenomenon. > > just a tought, what about SATA and SSD disk could that have some > influence on the latency? This seems unlikely but device substitution is the usual quick-n-dirty test. You could try running the LinuxCNC/LiveCD distribution from a USB thumbdrive. I've never heard anyone raise issues regarding SATA itself. > > But anyway i still think i have some powersave funktion running. I > noticed that the screen was black when i come back to the office, witch > i havent seen before. Ubuntu 10.04LTS offers a screen-saver mode that can be disabled via the menu bar. Select System.../Preferences.../Power Management and select "never" for the display sleep function. If this function is already disabled then I'm out of ideas. > I think i have to go back to check my bios version to see if there are > an uppgrade or alternative. It looks like 0130 is the current version (http://downloadcenter.intel.com/Detail_Desc.aspx?agr=Y&DwnldID=22377&lang=eng&wapkw=d525mw+bios). I have to say I'm skeptical that your BIOS is the cause of this mysterious spiking but I suppose upgrading is worth a try (some say upgrading the BIOS falls into the "if it ain't broke, don't fix it" category). > Regards Bjørn "Lykke til!" Regards, Kent ------------------------------------------------------------------------------ Own the Future-Intel® Level Up Game Demo Contest 2013 Rise to greatness in Intel's independent game demo contest. Compete for recognition, cash, and the chance to get your game on Steam. $5K grand prize plus 10 genre and skill prizes. Submit your demo by 6/6/13. http://p.sf.net/sfu/intel_levelupd2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
