Re: [Caml-list] minithread (was OCaml on Sony PS3)

["Mattias Engdegård" <mattias@virtutech.se>]

>However, (one of the) the CELL coprocessor -eg SPU) might be used to 
>implemented Ocaml garbage collector.
>
>A copying GC has to move quite a lot of data, and it could be possible 
>that CELL's coprocessors could be useful for that (assuming that they 
>access memory as quickly as the processor).

They don't so it isn't, and doing GC by a coprocessor that cannot
directly access the memory it manages does not sound very practical.

The PPE has the memories of all SPUs mapped into its physical address
space, so it could possibly do the GC for them. But again, given the
limited amount of SPU-private memory, it would probably not be a useful
approach.

Better use of the SPUs would be to run computations that can use manual
memory management (perhaps not using a heap at all), operating on small
chunks of data at a time. Such computations could be described in
a simpler language that is more amenable to parallelisation.

>I still think that SPU on PS3 are only useful for games, or specialized 
>(e.g. graphical) applications.

Maybe, but there are cell blades with more reasonable amounts of
memory, and for experimentation regarding how to use the processor, a
PS3 goes quite far and is very economical. Ground-breaking science has
been made in less than 256 MB.