Github user NicoK commented on a diff in the pull request:
https://github.com/apache/flink/pull/4509#discussion_r152852133
--- Diff:
flink-runtime/src/main/java/org/apache/flink/runtime/io/network/partition/consumer/RemoteInputChannel.java
---
@@ -572,20 +560,53 @@ void addExclusiveBuffer(Buffer buffer) {
exclusiveBuffers.add(buffer);
}
- Buffer takeExclusiveBuffer() {
- return exclusiveBuffers.poll();
- }
-
void addFloatingBuffer(Buffer buffer) {
floatingBuffers.add(buffer);
}
- Buffer takeFloatingBuffer() {
- return floatingBuffers.poll();
+ /**
+ * Add the exclusive buffer into the queue, and recycle one
floating buffer if the
+ * number of available buffers in queue is more than required
amount.
+ *
+ * @param buffer The exclusive buffer of this channel.
+ * @return Whether to recycle one floating buffer.
+ */
+ boolean maintainTargetSize(Buffer buffer) {
+ exclusiveBuffers.add(buffer);
+
+ if (getAvailableBufferSize() > numRequiredBuffers) {
+ Buffer floatingBuffer = floatingBuffers.poll();
+ floatingBuffer.recycle();
+ return true;
+ } else {
+ return false;
+ }
}
- int getFloatingBufferSize() {
- return floatingBuffers.size();
+ /**
+ * Take the floating buffer first if possible.
+ */
+ @Nullable
+ Buffer takeBuffer() {
--- End diff --
please explain when the result may be `null`
---
