Please note the block where cleanUpAllAllocatedMemory() is called:
} finally {
val freedMemory = taskMemoryManager.cleanUpAllAllocatedMemory()
if (freedMemory > 0) {
I think the intention is that allocated memory should have been freed by
the time we reach the finally block in normal program execution.
Hence the check for the return value for memory leak.
Experts may have better explanation.
On Mon, Oct 12, 2015 at 12:28 AM, Lei Wu <wulei.bj...@gmail.com> wrote:
> Dear all,
>
> I'm reading source code of TaskMemoryManager.java and I got stuck in the
> last function, that is cleanUpAllAllocatedMemory. What confuses me is the
> comments for this function : "A non-zero return value can be used to detect
> memory leaks".
>
> And from Executor.scala where this function is called, the code is like
> this :
> val freedMemory = taskMemoryManager.cleanUpAllAllocatedMemory()
> if(freedMemory > 0) {
> val errMsg = "Managed memory leak detected; ..."
> }
>
> My question is : this function cleanUpAllAllocatedMemory is used to clean
> up all the allocated memory and pages, and computes the bytes that are
> freed. Of course this value will be greater than 0 since we consumed that
> many amount of memory. What's the logic of detecting memory leak by
> checking this returned value is greater than 0?
>
