As you undoubtedly know, my scheduler branch has been merged a month ago. Also, some important changes has been made since, including bug fixes and performance improvements. It is now time to sum up what already has been done, and show some long promised benchmark results. There are still some issues that need to be addressed, but I do not think that any of them is a major one.
Most of the interesting work had already been done when I wrote my last report. The rest of my contract time was mostly spent tweaking, fixing and improving. However, in order to make this task easier I implemented very simple profiler which, when enabled, collects data regarding time taken to execute each function. Not wanting to spent to much writing this profiler, which is merely a tool, I have chosen the simplest approach that requires each function the profiler is to recognize to include macro SCHEDULER_ENTER_FUNCTION(). Additional and very important advantage of this solution is that the profiler is aware of inlined functions as well what would not be the case if the profiler relied solely on the information available at run time. As a result I got a very useful tool that is able to show me statistics: number of calls, total inclusive time, total exclusive time, average inclusive time per call and average exclusive time per call.
This is a companion discussion topic for the original entry at https://www.haiku-os.org/blog/pawe%C5%82_dziepak/2014-02-18_new_scheduler_merged/