id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
12	Unused array computations lead to memory leaks	tmcdonell		"The CUDA backend uses explicit reference tracking for device arrays. However, if the result of a computation is not used, it may not be released until the entire CUDA environment is closed down. This is evident for computations under `Let2`, but may exist more generally. In the example below, we modify the `runCUDA` function display any active memory records on finalisation.

{{{
test_scan = do
  let xs :: Acc (Vector Int) = use $ fromList 10 [0..]
      expr = Acc.scanl (+) 0 xs

  putStrLn ""scan""
  print =<< CUDA.run (Prelude.fst expr)

  putStrLn ""reduction""
  print =<< CUDA.run (Prelude.snd expr)
}}}

Results in:

{{{
*Test> test_scan
scan
 91488264:=MemoryEntry {_refcount = 0, _memsize = 4, _arena = 1049088}

Array 10 [0,0,1,3,6,10,15,21,28,36]
reduction
 118558728:=MemoryEntry {_refcount = 0, _memsize = 40, _arena = 1048832}

Array () [45]
}}} "	defect	closed	major		CUDA backend	0.8.0.0	fixed