MrQuansy commented on code in PR #14201: URL: https://github.com/apache/iotdb/pull/14201#discussion_r1863023436
########## iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/utils/binaryallocator/AdaptiveWeightedAverage.java: ########## @@ -0,0 +1,78 @@ +/* + * 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.iotdb.commons.utils.binaryallocator; + +import static java.lang.Math.max; + +public class AdaptiveWeightedAverage { + private float average; + private int sampleCount; + private final int weight; + private boolean isOld; // Enable to have enough historical data + private final int OLD_THRESHOLD = 100; + + public AdaptiveWeightedAverage(int weight) { + this.weight = weight; + average = 0f; + sampleCount = 0; + } + + public void sample(int newSample) { Review Comment: The EWMA implementation in com.codahale.metrics introduces extra work to improve concurrent performance, which wastes additional memory and reduces update performance. We don't need to consider concurrency issues here. BTW, the AdaptiveWeightedAverage is modified from JDK17 source codes. However, I made some modifications after discovering that memory allocation and deallocation occurs in cycles, such as before and after a request completes. Therefore, the active memory volume fluctuates significantly, so we calculate a moving average based on the peak active memory within each evictor cycle. -- 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]
