| /* |
| * 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.skywalking.oap.meter.analyzer.dsl.counter; |
| |
| import com.google.common.collect.ImmutableMap; |
| import com.google.common.collect.Maps; |
| import io.vavr.Tuple; |
| import io.vavr.Tuple2; |
| import java.util.Map; |
| import java.util.PriorityQueue; |
| import java.util.Queue; |
| import lombok.AccessLevel; |
| import lombok.EqualsAndHashCode; |
| import lombok.RequiredArgsConstructor; |
| import lombok.ToString; |
| |
| /** |
| * CounterWindow stores a series of counter samples in order to calculate the increase |
| * or instant rate of increase. |
| * |
| */ |
| @RequiredArgsConstructor(access = AccessLevel.PRIVATE) |
| @ToString |
| @EqualsAndHashCode |
| public class CounterWindow { |
| |
| public static final CounterWindow INSTANCE = new CounterWindow(); |
| |
| private final Map<ID, Tuple2<Long, Double>> lastElementMap = Maps.newHashMap(); |
| private final Map<ID, Queue<Tuple2<Long, Double>>> windows = Maps.newHashMap(); |
| |
| public Tuple2<Long, Double> increase(String name, ImmutableMap<String, String> labels, Double value, long windowSize, long now) { |
| ID id = new ID(name, labels); |
| if (!windows.containsKey(id)) { |
| windows.put(id, new PriorityQueue<>()); |
| } |
| |
| Queue<Tuple2<Long, Double>> window = windows.get(id); |
| window.offer(Tuple.of(now, value)); |
| long waterLevel = now - windowSize; |
| Tuple2<Long, Double> peek = window.peek(); |
| if (peek._1 > waterLevel) { |
| return peek; |
| } |
| |
| Tuple2<Long, Double> result = peek; |
| while (peek._1 < waterLevel) { |
| result = window.poll(); |
| peek = window.element(); |
| } |
| |
| // Choose the closed slot to the expected timestamp |
| if (waterLevel - result._1 <= peek._1 - waterLevel) { |
| return result; |
| } |
| |
| return peek; |
| } |
| |
| public Tuple2<Long, Double> pop(String name, ImmutableMap<String, String> labels, Double value, long now) { |
| ID id = new ID(name, labels); |
| |
| Tuple2<Long, Double> element = Tuple.of(now, value); |
| Tuple2<Long, Double> result = lastElementMap.get(id); |
| lastElementMap.put(id, element); |
| if (result == null) { |
| return element; |
| } |
| return result; |
| } |
| |
| public void reset() { |
| windows.clear(); |
| } |
| } |