On Tue, Oct 16, 2012 at 6:34 AM, <[email protected]> wrote: > Hello Arnaud, Charles, > > regarding the nut_clock_* iface unit testing, > I came to the following conclusion: > > 1/ It is IMO generally impossible to do deterministic > unit test; the problem in question is inherently > non-deterministic (I mean non-det. by nature). > Justification: the main reason is that we can't > perfectly predict the CPU time spent on computation, > mainly because we have multi-tasking; there might > be any number of context switches between almost > any states, so if we measure time with us/ns precisions, > we can't expect fitting times at that scale.
As I understand it, the more important thing to test is just whether a timer fires in roughly the correct amount of time, rather than whether it is precise. A tolerance of +/- 10% for times measured in seconds should be good enough for catching obvious errors, without being sensitive to system load. -- - Charles Lepple _______________________________________________ Nut-upsdev mailing list [email protected] http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/nut-upsdev
