garbage collection invokation, query functions for realtime

[centaurian_slug]

how about a function such as this:- invokeGarbageCollector :: IO (int,int)

which can be called in a "main loop" for interactive realtime application to ensure garbage does not build up between frames. returning (bytes used,bytes free) would give scope for making caching/throttling decisions. perhaps further options for passing a number of generations to affect, or an allowed amount of memory to move.

[centaurian_slug]

some say manual GC invokation is never needed , whilst others say an application can benefit from running a full cycle after a major change ('new document..') the point about realtime is to be able to have information and hints relating to the passage of time in the program structure. in an animation loop one has a clear cycle where behaviour must be consistent.

[simonmar]

We already have this:

• http://www.haskell.org/ghc/docs/latest/html/libraries/base-4.5.1.0/System-Mem.html
• http://www.haskell.org/ghc/docs/latest/html/libraries/base-4.5.1.0/GHC-Stats.html