* Frank Rowand <frank.rowand@xxxxxxxxxxx> wrote: > On 12/20/11 03:08, Ingo Molnar wrote: > > > > (Cc:-ing Arnaldo on this as well.) > > > > * Mathieu Desnoyers <compudj@xxxxxxxxxxxxxxxxxx> wrote: > > > > < snip > > > > I think your concentration on ABIs is missing a very fundamental > > property of instrumentation: > > > > the life-time and persistence of instrumentation data is > > typically very short ('days' is already an exception - typical > > is minutes, at most hours), and for that reason we havent been > > getting much pressure from users to maintain a perf.data ABI - > > but we are doing it nevertheless. > > > > Instrumentation is fundamentally about the 'here and now' and so > > it fundamentally differs from things like backup formats and > > database formats. An ABI does not hurt and we are maintaining > > it, but you are overrating its importance significantly. > > Just to provide visibility to a different use case... > > The life time of my data is typically weeks, months, or years > (though I am not likely to re-process year old raw data). I'm not saying that it's absolutely never done: for example monitoring/logging on a production box and evaluating events only once per month would certainly qualify. I just say that the overwhelming majority of usecases utilize traces on a short time-span and that we must keep the common usecase in mind when supporting not so common usecases. It's the same deal as with -rt: compared to the 'normal' usage of Linux -rt is somewhat of a special case - yet it's still something very much worth doing, as long as the main usecase is always kept in mind. Thanks, Ingo _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel