Ferrari6 commented on a change in pull request #7409: URL: https://github.com/apache/pinot/pull/7409#discussion_r705932231
########## File path: pinot-common/src/main/java/org/apache/pinot/common/function/JsonPathMapCache.java ########## @@ -0,0 +1,61 @@ +/** + * 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.pinot.common.function; + +import com.jayway.jsonpath.JsonPath; +import com.jayway.jsonpath.spi.cache.Cache; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.ConcurrentMap; + +/** + * This cache for avoiding repeatedly compiling JSON path string when using jsonPathXXX transformations + * + * <p>The existing jay way LRUCache is very inefficient, It will cause + * a lot of unnecessary lock waits during high concurrent data ingestion, + * and LRU mechanism is inappropriate for Pinot bounded size of the + * transformation config, so we should use this simple Map cache instead + * of it. Review comment: Guava Cache uses `recencyQueue` to record cache accesses. A large number of `CAS` enqueue operations generated by hotkeys will cause CPU consumption, and this synchronous recording will also slow down cache reading. I think maybe [Caffeine Cache](https://github.com/ben-manes/caffeine) is a good choice. Its Striped-RingBuffer design is more efficient for GC and CPU usage. And its API is very similar to Guava Cache. -- 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: commits-unsubscr...@pinot.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org
