David, I followed your suggestion and I think the finalizers for FPS are not running. Please take a look at http://wagerlabs.com/Bar.hs to see what I mean. I had to modify the FPS export list to expose the constructor but that's the only change I made. The other useful tidbits are: -- (internal) GC wrapper of mallocForeignPtrArray mallocForeignPtr :: Int -> IO (ForeignPtr Word8) mallocForeignPtr l = when (l > 1000000) performGC >> mallocForeignPtrArray l and createPS :: Int -> (Ptr Word8 -> IO ()) -> FastString createPS l write_ptr = unsafePerformIO $ do fp <- mallocForeignPtr l withForeignPtr fp $ \p -> write_ptr p return $ PS fp 0 l I replaced mallocForeignPtr with a call to mallocForeignBytes but that did not make a difference, the finalizers still don't run. Joel On Nov 5, 2005, at 4:57 PM, David Roundy wrote:
You can attach a print message to the finalizer and also print a message out when creating the string. I've found this to be helpful at times.