Github user NicoK commented on a diff in the pull request:
https://github.com/apache/flink/pull/4509#discussion_r152280350
--- Diff:
flink-runtime/src/test/java/org/apache/flink/runtime/io/network/partition/consumer/RemoteInputChannelTest.java
---
@@ -301,81 +306,388 @@ public void testProducerFailedException() throws
Exception {
}
/**
- * Tests {@link RemoteInputChannel#recycle(MemorySegment)}, verifying
the exclusive segment is
- * recycled to available buffers directly and it triggers notify of
announced credit.
+ * Tests to verify that the input channel requests floating buffers
from buffer pool
+ * in order to maintain backlog + initialCredit buffers available once
receiving the
+ * sender's backlog, and registers as listener if no floating buffers
available.
*/
@Test
- public void testRecycleExclusiveBufferBeforeReleased() throws Exception
{
- final SingleInputGate inputGate = mock(SingleInputGate.class);
- final RemoteInputChannel inputChannel =
spy(createRemoteInputChannel(inputGate));
+ public void testRequestFloatingBufferOnSenderBacklog() throws Exception
{
+ // Setup
+ final NetworkBufferPool networkBufferPool = new
NetworkBufferPool(12, 32, MemoryType.HEAP);
+ final SingleInputGate inputGate = createSingleInputGate();
+ final RemoteInputChannel inputChannel =
createRemoteInputChannel(inputGate);
+ try {
+ final int numFloatingBuffers = 10;
+ final BufferPool bufferPool =
spy(networkBufferPool.createBufferPool(numFloatingBuffers, numFloatingBuffers));
+ inputGate.setBufferPool(bufferPool);
+
+ // Assign exclusive segments to the channel
+ final int numExclusiveBuffers = 2;
+
inputGate.setInputChannel(inputChannel.partitionId.getPartitionId(),
inputChannel);
+ inputGate.assignExclusiveSegments(networkBufferPool,
numExclusiveBuffers);
+
+ assertEquals("There should be " + numExclusiveBuffers +
" buffers available in the channel",
+ numExclusiveBuffers,
inputChannel.getNumberOfAvailableBuffers());
- // Recycle exclusive segment
-
inputChannel.recycle(MemorySegmentFactory.allocateUnpooledSegment(1024,
inputChannel));
+ // Receive the producer's backlog
+ inputChannel.onSenderBacklog(8);
- assertEquals("There should be one buffer available after
recycle.",
- 1, inputChannel.getNumberOfAvailableBuffers());
- verify(inputChannel, times(1)).notifyCreditAvailable();
+ // Request the number of floating buffers by the
formula of backlog + initialCredit - availableBuffers
+ verify(bufferPool, times(8)).requestBuffer();
+ verify(bufferPool,
times(0)).addBufferListener(inputChannel);
+ assertEquals("There should be 10 buffers available in
the channel",
+ 10, inputChannel.getNumberOfAvailableBuffers());
-
inputChannel.recycle(MemorySegmentFactory.allocateUnpooledSegment(1024,
inputChannel));
+ inputChannel.onSenderBacklog(11);
- assertEquals("There should be two buffers available after
recycle.",
- 2, inputChannel.getNumberOfAvailableBuffers());
- // It should be called only once when increased from zero.
- verify(inputChannel, times(1)).notifyCreditAvailable();
+ // Need extra three floating buffers, but only two
buffers available in buffer pool, register as listener as a result
+ verify(bufferPool, times(11)).requestBuffer();
+ verify(bufferPool,
times(1)).addBufferListener(inputChannel);
+ assertEquals("There should be 12 buffers available in
the channel",
+ 12, inputChannel.getNumberOfAvailableBuffers());
+
+ inputChannel.onSenderBacklog(12);
+
+ // Already in the status of waiting for buffers and
will not request any more
+ verify(bufferPool, times(11)).requestBuffer();
+ verify(bufferPool,
times(1)).addBufferListener(inputChannel);
+
--- End diff --
Can you also verify the behaviour when the buffers become available? That
is, create the `bufferPool` with `numFloatingBuffers+1` buffers initially, take
one of them right after the creation, then continue as is and here `recycle()`
this buffer so that the channel should get it via the buffer listener.
Actually, it might even be useful to not only wait for 1 missing buffer,
but to change the number so that is should receive 2 of them so that we test
that the listener is actually getting not only one.
---
