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What can causes a jitter at real-time tasks?

As long as no other real-time software or similar system-critical software is installed,  (almost) nothing exists, which interrupts or delays the real-time task except:

- CLI = general interrupt blocked through Windows and drivers

(unfortunately, no software can do something against it; However, in Windows the blocking time is limited and almost the driver is responsible for this; in this case the respective driver has to be replaced; it is difficult to determine it, thus only possible by our support (in return of payment).

- WBINVD command to flush the entire internal cache

(according to experience, only by using Nvidia graphic drivers; only by replacement of the card with an ATI (AMD) the problem can be solved)

- C1E = Enhanced Power Save Mode of the CPU

(especially, the overdeveloped Intel CPUSs (i7, Xeon, ...) turns into the idle mode after short breaks, so that the wake up after a timer interrupt can take several milliseconds; that can be switched of in the BIOS (see CIE or similar) or the PC is not real-time capable.

Ordinary Windows activities cannot replace real-time task. Windows has the priority 1, whereas the RealTime tasks have the priorities from 1 to 255. DPC has no influence.

To achieve the goal to improve the real-time behavior, only the Dedicated Mode, which supports the exclusive use of single CPU cores in real-time. Without Windows influence the maximum jitter is less than < 1 us.