Lambda the Ultimate

Not strictly language related, more language implementation related, but worth bringing to the attention of LtU. Quoting from the abstract to this paper:

The Memory Pool System (MPS) is a very general, adaptable, flexible, reliable, and efficient memory management system. It permits the flexible combination of memory management techniques, supporting manual and automatic memory management, in-line allocation, finalization, weakness, and multiple simultaneous co-operating incremental generational garbage collections. It also includes a library of memory pool classes implementing specialized memory management policies.

Between 1994 and 2001, Harlequin (now part of Global Graphics) invested about thirty person-years of effort developing the MPS. The system contained many innovative techniques and abstractions which were kept secret. In 1997 Richard Brooksby, the manager and chief architect of the project, and Nicholas Barnes, a senior developer, left Harlequin to form their own consultancy company, Ravenbrook, and in 2001, Ravenbrook acquired the MPS technology from Global Graphics. We are happy to announce that we are publishing the source code and documentation under an open source licence. This paper gives an overview of the system.

(emphases mine) Good news for language implementors! Richard Brooksby gave a talk on the system at last night's SchemeUK meeting, and it sounds like it has a few killer features that would make it worth considering over a roll-your-own solution or an embedding of, say, the Boehm-Demers-Weiser collector.

(One interesting nugget of information he mentioned was that during development of the MLWorks compiler and system, before they started development of the MPS, they measured the cost of object allocation at two-and-a-half instructions per allocation, on average - two instructions for the allocation, and half an instruction for the garbage collection overhead! I don't think MPS is quite that efficient, but it certainly has a lot of potential.)