On 3/25/2013 9:56 AM, Bjørn wrote: > <snipping off previous discussion> now i have tested: boot with isolcpu(big > improvement in general latency but still spikes) > turn of smi, (improvement in general latency but still spikes) > 'idle=poll' and 'nohlt'(little or no effect) > > acpi = off and api=off (little or no effect) > > For the moment i have been running the system for 1,5 hour and have - > servothread interval 999655 and max jitter 4495 ns - base thread interval > 32069 max jitter 7190. > > witch i am very happy with, but if i run for several hours i still get spikes > up to 50000 and above. > i suspect Michael are right, the problem is related toidle/powersave states. > > I have no settings in bios to turn of ACPI > my bios is: MWNT10N.86A.0083.2011.0524.1600 > is this the same as others are running? and do you have option to turn off > ACPI from bios?
Bjørn: I don't have an Intel D525MW in my stable of motherboards but I do have an ASUS AT5NM10-I whose numbers I posted last year to the table of latency-test results in the Wiki. Your "pre-spike" numbers are reasonably consistent with the numbers I got. The "best" numbers I posted were obtained with hyperthreading turned off in the BIOS and isolcpus=1 set in the boot parameters. Nothing heroic. I did my tests long before list discussions brought out the importance of other parameter settings like idle=poll. In recent shortterm tests, I also have not seen dramatic improvements manipulating these parameters. Testing this ASUS board, I haven't seen the kinds of spikes you are experiencing. (Just for the record, I was testing LinuxCNC over 10.04LTS with the RTAI kernel). I'm curious to know what all is attached to your motherboard, especially anything attached via USB. I once had a motherboard that started misbehaving when I switched from a PS/2 mouse to a USB mouse and a number of us have seen the simple act of plugging in a USB thumbdrive cause bursts in latency numbers. Is it possible you have a peripheral interface/device that is waking up on the same time scale as the occurrence of your spikes? My system guy never failed to ask if the computer were plugged to a live outlet as his first step in diagnosing problems. Obviously your computer is plugged in but how are the power supply and the AC mains? Adequate, stable, clean? Regards, Kent ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_mar _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
