Difference between COMMITTED_HEAP_BYTES and PHYSICAL_MEMORY_BYTES

[Ranjan Banerjee]

Hi,
   Could someone please explain the difference between PHYSICAL_MEMORY_BYTES 
and COMMITTED_HEAP_BYTES.
    From my understanding COMMITTED_HEAP_BYTES is the xmx value in the tez 
container and PHYSICAL_MEMORY_BYTES is the actual memory used by the task.

But in my sample queries I see both of them to be the exact value, does this 
mean that my task is using 100% of the memory assigned? Some clarification 
would be greatly appreciated!

Thanks
Ranjan