sanha commented on a change in pull request #111: [NEMO-139, 6] Logic in the scheduler for appending jobs, Support RDD caching URL: https://github.com/apache/incubator-nemo/pull/111#discussion_r211446379
########## File path: common/src/main/java/edu/snu/nemo/common/ir/vertex/executionproperty/MarkerProperty.java ########## @@ -0,0 +1,46 @@ +/* + * Copyright (C) 2018 Seoul National University + * + * Licensed 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 edu.snu.nemo.common.ir.vertex.executionproperty; + +import edu.snu.nemo.common.ir.executionproperty.VertexExecutionProperty; + +/** + * A property represents that a vertex annotated with this property should be regarded as a kind of "marker" and + * doesn't process any data. + * Attaching this property makes runtime to not schedule this vertex. + * This kind of vertices is needed when some data have to be written before it's usage is not determined yet + * (e.g., for caching). + */ +public final class MarkerProperty extends VertexExecutionProperty<Boolean> { Review comment: If a vertex is annotated as a `MarkerProperty` (or `DoNotScheduleProperty`), the vertex should not be scheduled to any executor (forever). It will act as a simple marker to construct an edge (and the data in the edge). In contrast, the barrier vertex is scheduled to an executor, collects the metric of data, sends the metric data to master, becomes `ON_HOLD` state, and is completed after a dynamic optimization with the metric. It seems that there is no reason to merge the two property. ---------------------------------------------------------------- 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
