jeongyooneo commented on a change in pull request #2: [NEMO-7] Intra-TaskGroup pipelining URL: https://github.com/apache/incubator-nemo/pull/2#discussion_r172766716
########## File path: runtime/executor/src/main/java/edu/snu/nemo/runtime/executor/TaskGroupExecutor.java ########## @@ -60,13 +55,36 @@ private final DataTransferFactory channelFactory; private final MetricCollector metricCollector; - /** - * Map of task IDs in this task group to their readers/writers. - */ - private final Map<String, List<InputReader>> physicalTaskIdToInputReaderMap; - private final Map<String, List<OutputWriter>> physicalTaskIdToOutputWriterMap; - - private boolean isExecutionRequested; + // Map of task ID to its intra-TaskGroup data pipe. + private final Map<Task, List<LocalPipe>> taskToInputPipesMap; + private final Map<Task, LocalPipe> taskToOutputPipeMap; // one and only one Pipe per task + // Readers/writers that deals with inter-TaskGroup data. + private final List<InputReader> inputReaders; + private final Map<Task, List<InputReader>> taskToInputReadersMap; + private final Map<Task, List<InputReader>> taskToSideInputReadersMap; + private final Map<Task, List<OutputWriter>> taskToOutputWritersMap; + private final Map<InputReader, List<Task>> inputReaderToTasksMap; + private final Map<String, Iterator> idToSrcIteratorMap; + private final Map<String, List<Task>> srcIteratorIdToTasksMap; + private final Map<String, List<Task>> iteratorIdToTasksMap; + private final LinkedBlockingQueue<Pair<String, DataUtil.IteratorWithNumBytes>> iteratorQueue; + private volatile Map<String, List<Task>> pipeIdToDstTasksMap; + private final Set<Transform> preparedTransforms; + private final Set<String> finishedTaskIds; Review comment: I don't think so. From the point of view of Task, it is not known the point where it consumed all the iterators. Even at the point when all iterators are received and consumed in `execute()`, there can exist some Tasks at downstream that haven't received it. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services