What is Outside JVM in Task manager UI in flink web ui?

Question

While monitoring a streaming job on flink ui I encountered outside JVM .

What exactly it is and what is count column ?

Answer 1

Outsize JVM refers to native memory used by flink TM. MemoryManager in flink TM will acquire native memory through ByteBuffer.allocateDirect() based on the congfiuration.

Count Column refers to number of buffers in the pool, decided by the number of calls to ByteBuffer.allocateDirect().