Github user anmolnar commented on a diff in the pull request: https://github.com/apache/zookeeper/pull/440#discussion_r161661577 --- Diff: src/java/main/org/apache/zookeeper/server/quorum/ProposalStats.java --- @@ -0,0 +1,70 @@ +/** + * 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.zookeeper.server.quorum; + +import com.codahale.metrics.ExponentiallyDecayingReservoir; +import com.codahale.metrics.Histogram; +import com.codahale.metrics.JmxReporter; +import com.codahale.metrics.MetricRegistry; +import com.codahale.metrics.Reservoir; +import com.codahale.metrics.Snapshot; +import org.apache.zookeeper.jmx.CommonNames; +import org.apache.zookeeper.jmx.MBeanRegistry; + +import static com.codahale.metrics.MetricRegistry.name; + +/** + * Provides real-time metrics on Leader's proposal size. + * The class uses a histogram included in Dropwizard metrics library with ExponentiallyDecayingReservoir. + * It provides stats of proposal sizes from the last 5 minutes with acceptable cpu/memory footprint optimized for streaming data. + */ +public class ProposalStats { + private final Histogram proposalSizes; + + ProposalStats() { + final MetricRegistry metrics = new MetricRegistry(); + Reservoir reservoir = new ExponentiallyDecayingReservoir(); --- End diff -- @afine Would you approve the PR with existing reservoir or do you still think it'd be better to go with configurable sliding window?
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