[FLINK-1801] [FLINK-1465] Network environment can start prior to Task…

…Manager in "disassociated" mode.

NetworkEnvironment allocates heavy network buffer pool on startup and supports
multiple associations / disassociations with the TaskManager actor.

Fix negative memory report by replacing overflowing ints with longs.

flink-runtime/src/main/java/org/apache/flink/runtime/io/network/ConnectionManager.java

@@ -30,7 +30,9 @@
  */
 public interface ConnectionManager {
 
- void start(ResultPartitionProvider partitionProvider, TaskEventDispatcher taskEventDispatcher, NetworkBufferPool networkbufferPool) throws IOException;
+ void start(ResultPartitionProvider partitionProvider,
+ TaskEventDispatcher taskEventDispatcher,
+ NetworkBufferPool networkbufferPool) throws IOException;
 
  /**
  * Creates a {@link PartitionRequestClient} instance for the given {@link ConnectionID}.

flink-runtime/src/main/java/org/apache/flink/runtime/io/network/LocalConnectionManager.java

@@ -22,20 +22,20 @@
 import org.apache.flink.runtime.io.network.netty.PartitionRequestClient;
 import org.apache.flink.runtime.io.network.partition.ResultPartitionProvider;
 
-import java.io.IOException;
-
 /**
  * A connection manager implementation to bypass setup overhead for task managers running in local
  * execution mode.
  */
 public class LocalConnectionManager implements ConnectionManager {
 
  @Override
- public void start(ResultPartitionProvider partitionProvider, TaskEventDispatcher taskEventDispatcher, NetworkBufferPool networkbufferPool) throws IOException {
+ public void start(ResultPartitionProvider partitionProvider,
+ TaskEventDispatcher taskEventDispatcher,
+ NetworkBufferPool networkbufferPool) {
  }
 
  @Override
- public PartitionRequestClient createPartitionRequestClient(ConnectionID connectionId) throws IOException {
+ public PartitionRequestClient createPartitionRequestClient(ConnectionID connectionId) {
  return null;
  }
 
@@ -48,6 +48,5 @@ public int getNumberOfActiveConnections() {
  }
 
  @Override
- public void shutdown() throws IOException {
- }
+ public void shutdown() {}
 }