Lemarais commented on a change in pull request #317: URL: https://github.com/apache/incubator-nemo/pull/317#discussion_r705809356
########## File path: common/src/main/java/org/apache/nemo/common/punctuation/Latencymark.java ########## @@ -0,0 +1,93 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ +package org.apache.nemo.common.punctuation; + +import java.io.Serializable; +import java.util.Objects; + +/** + * Latency mark is conveyor that has data for debugging. + * It is created only from source vertex and record the timestamp when it is created and taskId where it is created. Review comment: First of all, Pair of createdTaskId and timestamp indicates the starting point. For examples, -----------B----------- / \ A to E indicates tasks A ------------C-----------E dash indicates edges \ / A is a source, and E is a sink ------------D---------- Latencymark is created from task A with timestamp and createdTaskId. And the lastTaskId needs to follow each path. When Latencymark reached at task E, there are totally three path, A-B-E, A-C-E, A-D-E. And I want to know latency for each path. So I make it hold the previous task Id. So when Latencymark reached at task E, Task E received three latencymark. And the lastTaskId will be B, C, and E, respectively. Of course, The lastTaskId itself does not have a meaning, but I expected that we would know the latency for each path if we followed the lastTaskId. This part may be controversial and I think it will be okay to remove if it is deemed unnecessary. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
