HeapSize

Based on GHC.Datasize by Dennis Felsing

Documentation

recursiveSize :: a -> IO Int

Calculate the recursive size of GHC objects in Bytes. Note that the actual size in memory is calculated, so shared values are only counted once.

Call with recursiveSize $! 2 to force evaluation to WHNF before calculating the size.

Call with recursiveSize $!! "foobar" ($!! from Control.DeepSeq) to force full evaluation before calculating the size.

A garbage collection is performed before the size is calculated, because the garbage collector would make heap walks difficult.

This function works very quickly on small data structures, but can be slow on large and complex ones. If speed is an issue it's probably possible to get the exact size of a small portion of the data structure and then estimate the total size from that.

recursiveSizeNoGC :: a -> IO Int

Same as recursiveSize except without performing garbage collection first. Useful if you want to measure the size of many objects in sequence. You can call performGC once at first and then use this function to avoid multiple unnecessary garbage collections.

recursiveSizeNF :: NFData a => a -> IO Int

Calculate the recursive size of GHC objects in Bytes after calling Control.DeepSeq.force on the data structure to force it into Normal Form. Using this function requires that the data structure has an NFData typeclass instance.

closureSize :: a -> IO Int

Get the *non-recursive* size of an closure in words