[Haskell-cafe] Current heap size and other runtime statistics -- API for accessing in GHC?

[Andrew Coppin]

On 11/04/2011 12:52 AM, Don Stewart wrote:
> I'd like a proper FFI binding for getting at Stats.c dynamically. So I
> can write programs that determine their own stats about the GC and so
> on.

I have often wished that there was a much bigger API for interacting 
with the RTS. Currently, you can query how many capabilities there are, 
and you can request a (magor?) GC cycle. And that's *it*.

One can imagine a far richer API, with the ability to do things like set 
and query RTS flags, query the GHC version number and RTS "way", ask how 
much RAM is allocated to what, request a minor or magor GC, try to 
release RAM to the OS, pre-allocate RAM from the OS because you're about 
to use it, find out how many threads are running or how many sparks are 
queued, and so on.

Of course, I doubt anyone is going to implement it anytime soon...