Hello, I'm writing a library which will require many blocks of binary data of various sizes (some very large) to be stored in the heap. I'm a little worried about the effect this will have on the efficiency of garbage collection. I'm not sure how ghc gc works these days, but I seem to remember it's a copying collector by default. If so it seems a pity to waste time copying 10's of MBytes of binaries at each collection. The options I'm considering are.. (1) Use Haskell heap space Pros: Easy for me Cons: May slow down gc AFAICS I can't use anything like realloc Current FFI proposals seem to prevent me from directly accessing Haskell heap objects from C land (or have I misunderstood?). (2) Use C heap space Pros: Easy(ish) to use from C and Haskell ffi Cons: Unless C heaps have improved a lot since I last looked (which I doubt), it seems likely I will suffer from slow allocation and fragmentation problems. (3) Write my own "sliding" heap manager and use finalisers for garbage collection. Pros: Can tailor it to work exactly the way I want. Cons: More work for me, especially if I want the result to be portable across OS's. Might be a complete waste of time if my worries about ghc heap management are groundless :-) Any advice? Thanks -- Adrian Hey