Github user NicoK commented on a diff in the pull request:
https://github.com/apache/flink/pull/4499#discussion_r140821090
--- Diff:
flink-runtime/src/main/java/org/apache/flink/runtime/io/network/partition/consumer/RemoteInputChannel.java
---
@@ -183,18 +214,40 @@ void notifySubpartitionConsumed() {
}
/**
- * Releases all received buffers and closes the partition request
client.
+ * Releases all received and available buffers, closes the partition
request client.
*/
@Override
void releaseAllResources() throws IOException {
if (isReleased.compareAndSet(false, true)) {
+
+ final List<MemorySegment> recyclingSegments = new
ArrayList<>();
+
synchronized (receivedBuffers) {
Buffer buffer;
while ((buffer = receivedBuffers.poll()) !=
null) {
- buffer.recycle();
+ if (buffer.getRecycler() == this) {
+
recyclingSegments.add(buffer.getMemorySegment());
--- End diff --
1) I think, performance is not much of an issue here, as this is only
called during take-down of a connection and the overhead of `Buffer#recycle` is
actually not that much.
2) Sorry, but I don't get your concern. Why would you need an extra check
when using `buffer.recycle()` instead of
`exclusiveRecyclingSegments.add(buffer.getMemorySegment())`? There shouldn't be
anything special for the exclusive buffers in this regard compared to ordinary
buffers (which is the beauty of the design).
Let me give the example of how `LocalBufferPool` handles this inside
`lazyDestroy`: it returns every memory segment (one by one) with
`networkBufferPool.recycle()` and, at its end, it is calling
`networkBufferPool.destroyBufferPool()` so that the book-keeping inside the
`NetworkBufferPool` is updated and buffers may be re-distributed to other
`LocalBufferPool` instances.
We could do this similarly here: recycle one by one, then call some method
to update book-keeping and balancing inside `NetworkBufferPool`.
---
