On Dec 5 2012 9:03 AM, Kent A. Reed wrote: > On 12/5/2012 4:16 AM, EBo wrote: >> On Dec 4 2012 9:06 AM, Kent A. Reed wrote: >>> <...> If one is satisfied that the internal, latency-test approach >>> provides a reasonable metric, then it would be dead-simple to take >>> latency-test/latencyplot a step further, bin the results, and >>> derive >>> interesting measures from it. Like latency-test, one could provide >>> a >>> running tally of key measures or like the OSADL does for its >>> RT-Preempt, >>> one could draw histograms and analyze exhaustively on demand. >> I'm not a statistician, but have been involved with some wicked cool >> statistical analysis projects in the distant past. I wonder if >> there is >> anyone in the group who knows how to use R well enough to help >> design >> and set up a study to tease out various things like outliers, the >> spectral density, ... I am not sure what all, but that would be a >> formal >> way to get at what you are talking about. The nice thing is that R >> might already have the nasty bits like sapa, quantspec, spectralGP, >> or >> possibly BaSAR. I'm not realistically going to have the time to >> delve >> into this, but thought I would throw out the idea... >> >> EBo -- >> > > I love exploratory data analysis. Over the years it proved invaluable > first in my degree work (I owe my degree to it) and later in my > professional research. Fancy analysis---and R would be a great > tool---can come later, but always start with plots to get a feel for > the > problem at hand. > > I'm shooting for a histogram plot by this weekend.
Agreed. Most people are surprised at just how much leverage you can get by just taking the mean. Fancy or not, the questions I would like to see answered are: *) what is the mean and std of the the latencies. *) are there any outliers (blown constraints). This could get fancy quick, but anything simple to start would be more than fine. *) if there are any outliers are they grouped? By how much are they off? How often do they happen? Again, these questions could get advanced quick, but your histogram should allow us to visually inspect the results and make an intuitive guess. EBo -- ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
