Luca's meaningless thoughts  

I've just published the git repository of my D GC implementation: CDGC. The name stands for Concurrent D Garbage Collector but right now you may call it Configurable D Garbage Collector, as there is no concurrency at all yet, but the GC is configurable via environment variables :)

It's based on the Tango (0.99.9) basic GC, there are only few changes at the moment, probably the bigger ones are:

• Runtime configurability using environment variables.
• Logging of malloc()s and collections to easily get stats about time and space consumed by the GC (option malloc_stats_file [str] and collect_stats_file [str]).
• Precise heap scanning based on the patches published in bug 3463 (option conservative [bool]).
• Runtime configurable debug features (option mem_stomp [bool] and sentinel [bool]).
• Other non user-visible cleanups.

The configuration is done via the D_GC_OPTS environment variable, and the format is:

D_GC_OPTS=opt1=value:opt2=value:bool_opt:opt3=value

Where opt1, opt2, opt3 and bool_opt are option names and value is their respective values. Boolean options can omit the value (which means true) or use a value of 0 or 1 to express false and true respectively. String options have no limitations, except they can't have the : char in their values and they have a maximum value length (255 at this moment).

At the moment is a little slower than the Tango basic GC, because the precise scanning is done very naively and a lot of calls to findPool() are done. This will change in the future.

There is a lot of work to be done (cleanup, optimization and the concurrent part :), but I'm making it public because maybe someone could want to adapt some of the ideas or follow the development.

I've finally published my own git druntime repository. It has both branches, the one for D2 (the svn trunk, called master in my repo) and the one for D1 (D1.0 in svn, d1 in my repo).

For now, there are only changes in the master branch.