zsxwing commented on a change in pull request #31476: URL: https://github.com/apache/spark/pull/31476#discussion_r570666630
########## File path: sql/catalyst/src/main/java/org/apache/spark/sql/connector/CustomMetric.java ########## @@ -0,0 +1,38 @@ +/* + * 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.spark.sql.connector; + +import org.apache.spark.annotation.Evolving; + +/** + * A custom metric. Review comment: Since this is a public API, it would be great to add more information to explain how to use APIs as a developer. For example, - If I define my own `CustomMetric`, how does Spark use it? - If I define a metric type that doesn't support `sum`, for example, measure the executor jvm heap size, how does Spark handle it? - If my `PartitionReaderWithMetrics` returns metrics for a partition, will Spark combine them for partitions of a Spark job? - In the streaming case, how does Spark combine metrics from different micro batches? - If I would like to report metrics in driver, how do I do it? I feel you might need to build an interface similar to the private `SQLMetric`. ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
