On Sun, 22 September 2013 22:43:38 -0400, Theodore Ts'o wrote: > On Sun, Sep 22, 2013 at 08:16:23PM -0400, Jörn Engel wrote: > > How about we switch between the two mixing functions depending on the > > interrupt load? If this CPU has seen fewer than 1000 interrupts in > > the last second, use the better one, otherwise us the cheaper one? > > I guess the question here is whether it's worth it. On a 2.8 GHz > laptop Ivy Bridge chip the numbers are:
Then let us assume for now it is not worth it. When I finally get around to generating profiles for my insane system we can revisit the issue. > I am very strongly of the opinion that the number of systems where you > have an embedded system with that kind of inane interrupt rate is the > 0.00000000001% case. That would be one machine in 10^13? I doubt we have reached 10^13 machines running Linux in all of history, so a single example would defeat your very strong opinion. ;) Anyway, let me collect some real numbers before we argue any further. And thank you for your maintainership. It may not appear that way, but I have _very_ little to complain about in drivers/char/random.c. Jörn -- One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision. -- Bertrand Russell -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
