Hello Gergely,
2009/3/22 Patai Gergely
Last Summer, I also proposed a Google SOC project for profiling, called Parallel Profiling Support for GHC. This project was denied for the Google SOC mostly due to the scope of the project and the concern that the project would take far longer than the Summer. Yes, I'm aware of that trap. However, I think the ideas I proposed (rather vaguely, I have to admit) could be handled in three months, especially since I can familiarise myself with the relevant parts of the rts before actual work starts, and the first part of the task doesn't even require significant changes, if any.
ThreadScope: http://raintown.org/?page_id=132 I know about that one, that's another reason why I wanted to explore the area of more user-friendly space profiling instead: it seems somewhat neglected. Of course that might be because people don't feel an urgent need for more powerful tools, but I can't tell that without asking the community.
I do agree that a visualizer would be useful for space profiling (and all areas of profiling for that matter).
The EventLog framework (used by ThreadScope) is now available in the GHC RTS ($GHC_ROOT/rts/eventlog) and has been committed to GHC HEAD. Thanks for the pointer, I'll check it out.
Just to reiterate, make sure that the scope of your project is well-defined. :) Of course I intend to list some specific subtasks in my proposal, preferably the kind that makes life much easier with minimal changes to the codebase. :)
Be sure to include a schedule too. I think there was an example Google SOC project to follow as a guideline.
If you have any questions, feel free to ask. I'll see if I have some after looking at the code. For the time being there's only the one I'd ask anyone: how do you think space profiling could be made more convenient?
As I said above, I do think a visualizer for space profiling would be an improvement over the current log file output. I'll let you know if I think of some other suggestions. -- Donnie Jones