anuengineer commented on a change in pull request #798: HDDS-1499. OzoneManager Cache. URL: https://github.com/apache/hadoop/pull/798#discussion_r282168861
########## File path: hadoop-hdds/common/src/main/java/org/apache/hadoop/utils/db/cache/PartialTableCache.java ########## @@ -0,0 +1,96 @@ +/* + * 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.hadoop.utils.db.cache; + +import java.util.Iterator; +import java.util.TreeSet; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.ExecutorService; +import java.util.concurrent.Executors; + +import org.apache.hadoop.classification.InterfaceAudience.Private; +import org.apache.hadoop.classification.InterfaceStability.Evolving; + + + +/** + * This is used for the tables where we don't want to cache entire table in + * in-memory. + */ +@Private +@Evolving +public class PartialTableCache<CACHEKEY, CACHEVALUE> + implements TableCache<CACHEKEY, CACHEVALUE>{ Review comment: Not sure if you have seen this, https://github.com/facebook/rocksdb/wiki/Block-Cache We already do this cache control in the RockDB. I am not sure if we should do this twice. Unless you have a lookup problem which cannot be solved by hashing or prefix lookup, we will have more efficient usage of memory by relying on the underlying layer and more over having a unified cache layer will lead to better cache layer utilization. ---------------------------------------------------------------- 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 With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org
