Hi,
Philippe Gerum wrote:
The problem might be that spurious LXRT load induced by such sleeping
state might keep increasing over time, at least to the point where they
become significant wrt hackbench figures. In fact, any LXRT task running
in hard mode also sleeps in TASK_UNINTERRUPTIBLE mode after it has been
stolen away from the Linux scheduler; this impacts the Linux loadavg the
same way, but in this case, this could be construed as a real load since
the RT side actually runs here. So we have two opposite situations
charged for the same result.
I did not specifically investigate the matter, but I suspect that such
results would carry too much uncertainty for proper interpretation.
Thanks for the explanation!
Then I shall remove them from the LiveCD and DB.
Or should I better remove that data from the DB? Or can
I use some other metric for calculating load (which is valid
when running RTAI/LXRT)?
Using the execution time figures available from /proc/rtai/ scheduler
might be a better information than Linux's loadavg for LXRT, even if
they don't refer to the same kind of load.
I will add those.
What data should best be added from the other tests (preempt,switch)?
Interesting data that immediately come to my mind are:
o interrupt propagation time in the Adeos layer (Adeos needs to provide
the info here -- I'm going to add that in the next release);
I'll add them as soon as they are available.
o for x86, average programming time of the 8254, especially under
saturated bus conditions (e.g. dd if=/dev/zero of=<hdd-file> count=X
bs=1M); this directly impacts the quality of the scheduling latency
calibration in one-shot mode;
Does dd if=/dev/hdc of=/dev/null count=X bs=1M give a
similar effect with respect to bus saturation?
With friendly regards,
Takis
--
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Panagiotis Issaris
Katholieke Universiteit Leuven
Division Production Engineering,
Machine Design and Automation
Celestijnenlaan 300B [EMAIL PROTECTED]
B-3001 Leuven Belgium http://www.mech.kuleuven.ac.be/pma
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