com.alibaba.wasp.fserver.MetricsFServerWrapperImpl.java Source code

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Here is the source code for com.alibaba.wasp.fserver.MetricsFServerWrapperImpl.java

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/**
 * Copyright The Apache Software Foundation
 *
 * 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 com.alibaba.wasp.fserver;

import com.alibaba.wasp.ServerName;
import com.alibaba.wasp.fserver.metrics.MetricsFServerWrapper;
import com.alibaba.wasp.metrics.MetricsExecutor;
import com.alibaba.wasp.zookeeper.ZooKeeperWatcher;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;

import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

/**
 * Impl for exposing FServer Information through Hadoop's metrics 2 system.
 */
public class MetricsFServerWrapperImpl implements MetricsFServerWrapper {
    public static final Log LOG = LogFactory.getLog(MetricsFServerWrapperImpl.class);

    public static final int PERIOD = 15;

    private final FServer fserver;

    private ScheduledExecutorService executor;
    private Runnable runnable;

    private volatile double requestsPerSecond = 0.0;
    private volatile double readRequestsPerSecond = 0.0;
    private volatile double writeRequestsPerSecond = 0.0;

    public MetricsFServerWrapperImpl(final FServer fserver) {
        this.fserver = fserver;
        this.executor = MetricsExecutor.getExecutor();
        this.runnable = new FServerMetricsWrapperRunnable();
        this.executor.scheduleWithFixedDelay(this.runnable, PERIOD, PERIOD, TimeUnit.SECONDS);
    }

    @Override
    public String getServerName() {
        ServerName serverName = fserver.getServerName();
        if (serverName == null) {
            return "";
        }
        return serverName.getServerName();
    }

    @Override
    public String getClusterId() {
        return fserver.getClusterId();
    }

    @Override
    public String getZookeeperQuorum() {
        ZooKeeperWatcher zk = fserver.getZooKeeper();
        if (zk == null) {
            return "";
        }
        return zk.getQuorum();
    }

    @Override
    public long getStartCode() {
        return fserver.getStartcode();
    }

    @Override
    public long getNumOnlineEntityGroups() {
        return fserver.getNumberOfOnlineEntityGroups();
    }

    @Override
    public double getRequestsPerSecond() {
        return this.requestsPerSecond;
    }

    @Override
    public double getReadRequestsPerSecond() {
        return this.readRequestsPerSecond;
    }

    @Override
    public double getWriteRequestsPerSecond() {
        return this.writeRequestsPerSecond;
    }

    @Override
    public void forceRecompute() {
        this.runnable.run();
    }

    /**
     * This is the runnable that will be executed on the executor every PERIOD
     * number of seconds It will take metrics/numbers from all of the entity
     * pgropus and use them to compute point in time metrics.
     */
    public class FServerMetricsWrapperRunnable implements Runnable {

        private long lastRan = 0;
        private long lastReadRequestCount = 0;
        private long lastWriteRequestCount = 0;

        @Override
        synchronized public void run() {

            long tempReadRequestsCount = 0;
            long tempWriteRequestsCount = 0;

            for (EntityGroup eg : fserver.getOnlineEntityGroupsLocalContext()) {
                tempReadRequestsCount += eg.readRequestsCount.get();
                tempWriteRequestsCount += eg.writeRequestsCount.get();
            }

            // Compute the number of requests per second
            long currentTime = EnvironmentEdgeManager.currentTimeMillis();

            // assume that it took PERIOD seconds to start the executor.
            // this is a guess but it's a pretty good one.
            if (lastRan == 0) {
                lastRan = currentTime - (PERIOD * 1000);
            }

            // If we've time traveled keep the last requests per second.
            if ((currentTime - lastRan) > 10) {
                readRequestsPerSecond = (tempReadRequestsCount - lastReadRequestCount)
                        / ((currentTime - lastRan) / 1000.0);
                writeRequestsPerSecond = (tempWriteRequestsCount - lastWriteRequestCount)
                        / ((currentTime - lastRan) / 1000.0);
                requestsPerSecond = readRequestsPerSecond + writeRequestsPerSecond;
                lastReadRequestCount = tempReadRequestsCount;
                lastWriteRequestCount = tempWriteRequestsCount;
            }
            lastRan = currentTime;

            // Copy over computed values so that no thread sees half computed values.
        }
    }

}