Method flush

netty/src/main/java/io/grpc/netty/WriteQueue.java:122–153

Process the queue of commands and dispatch them to the stream. This method is only called in the event loop

()

   * called in the event loop
   */
  private void flush() {
    try (TaskCloseable ignore = PerfMark.traceTask("WriteQueue.periodicFlush")) {
      QueuedCommand cmd;
      int i = 0;
      boolean flushedOnce = false;
      while ((cmd = queue.poll()) != null) {
        cmd.run(channel);
        if (++i == DEQUE_CHUNK_SIZE) {
          i = 0;
          // Flush each chunk so we are releasing buffers periodically. In theory this loop
          // might never end as new events are continuously added to the queue, if we never
          // flushed in that case we would be guaranteed to OOM.
          try (TaskCloseable ignore2 = PerfMark.traceTask("WriteQueue.flush0")) {
            channel.flush();
          }
          flushedOnce = true;
        }
      }
      // Must flush at least once, even if there were no writes.
      if (i != 0 || !flushedOnce) {
        try (TaskCloseable ignore2 = PerfMark.traceTask("WriteQueue.flush1")) {
          channel.flush();
        }
      }
    } finally {
      // Mark the write as done, if the queue is non-empty after marking trigger a new write.
      scheduled.set(false);
      if (!queue.isEmpty()) {
        scheduleFlush();
      }
    }
  }

  private static class RunnableCommand implements QueuedCommand {
    private final Runnable runnable;