org.apache.accumulo.server.monitor.Monitor.java Source code

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/*
 * 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.accumulo.server.monitor;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import org.apache.accumulo.core.Constants;
import org.apache.accumulo.core.client.Instance;
import org.apache.accumulo.core.client.impl.MasterClient;
import org.apache.accumulo.core.conf.AccumuloConfiguration;
import org.apache.accumulo.core.conf.Property;
import org.apache.accumulo.core.gc.thrift.GCMonitorService;
import org.apache.accumulo.core.gc.thrift.GCStatus;
import org.apache.accumulo.core.master.thrift.Compacting;
import org.apache.accumulo.core.master.thrift.MasterClientService;
import org.apache.accumulo.core.master.thrift.MasterMonitorInfo;
import org.apache.accumulo.core.master.thrift.TableInfo;
import org.apache.accumulo.core.master.thrift.TabletServerStatus;
import org.apache.accumulo.core.security.SecurityUtil;
import org.apache.accumulo.core.util.Daemon;
import org.apache.accumulo.core.util.LoggingRunnable;
import org.apache.accumulo.core.util.Pair;
import org.apache.accumulo.core.util.ServerServices;
import org.apache.accumulo.core.util.ServerServices.Service;
import org.apache.accumulo.core.util.ThriftUtil;
import org.apache.accumulo.core.util.UtilWaitThread;
import org.apache.accumulo.core.zookeeper.ZooUtil;
import org.apache.accumulo.fate.zookeeper.ZooUtil.NodeExistsPolicy;
import org.apache.accumulo.server.Accumulo;
import org.apache.accumulo.server.ServerOpts;
import org.apache.accumulo.server.client.HdfsZooInstance;
import org.apache.accumulo.server.conf.ServerConfiguration;
import org.apache.accumulo.server.fs.VolumeManager;
import org.apache.accumulo.server.fs.VolumeManagerImpl;
import org.apache.accumulo.server.monitor.servlets.DefaultServlet;
import org.apache.accumulo.server.monitor.servlets.GcStatusServlet;
import org.apache.accumulo.server.monitor.servlets.JSONServlet;
import org.apache.accumulo.server.monitor.servlets.LogServlet;
import org.apache.accumulo.server.monitor.servlets.MasterServlet;
import org.apache.accumulo.server.monitor.servlets.OperationServlet;
import org.apache.accumulo.server.monitor.servlets.ProblemServlet;
import org.apache.accumulo.server.monitor.servlets.ShellServlet;
import org.apache.accumulo.server.monitor.servlets.TServersServlet;
import org.apache.accumulo.server.monitor.servlets.TablesServlet;
import org.apache.accumulo.server.monitor.servlets.VisServlet;
import org.apache.accumulo.server.monitor.servlets.XMLServlet;
import org.apache.accumulo.server.monitor.servlets.trace.ListType;
import org.apache.accumulo.server.monitor.servlets.trace.ShowTrace;
import org.apache.accumulo.server.monitor.servlets.trace.Summary;
import org.apache.accumulo.server.problems.ProblemReports;
import org.apache.accumulo.server.problems.ProblemType;
import org.apache.accumulo.server.security.SystemCredentials;
import org.apache.accumulo.server.util.EmbeddedWebServer;
import org.apache.accumulo.server.zookeeper.ZooReaderWriter;
import org.apache.accumulo.trace.instrument.Tracer;
import org.apache.log4j.Logger;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;

import com.google.common.net.HostAndPort;

/**
 * Serve master statistics with an embedded web server.
 */
public class Monitor {
    private static final Logger log = Logger.getLogger(Monitor.class);

    public static final int REFRESH_TIME = 5;
    private static long lastRecalc = 0L;
    private static double totalIngestRate = 0.0;
    private static double totalIngestByteRate = 0.0;
    private static double totalQueryRate = 0.0;
    private static double totalScanRate = 0.0;
    private static double totalQueryByteRate = 0.0;
    private static long totalEntries = 0L;
    private static int totalTabletCount = 0;
    private static int onlineTabletCount = 0;
    private static long totalHoldTime = 0;
    private static long totalLookups = 0;
    private static int totalTables = 0;

    private static class MaxList<T> extends LinkedList<Pair<Long, T>> {
        private static final long serialVersionUID = 1L;

        private long maxDelta;

        public MaxList(long maxDelta) {
            this.maxDelta = maxDelta;
        }

        @Override
        public boolean add(Pair<Long, T> obj) {
            boolean result = super.add(obj);

            if (obj.getFirst() - get(0).getFirst() > maxDelta)
                remove(0);

            return result;
        }

    }

    private static final int MAX_TIME_PERIOD = 60 * 60 * 1000;
    private static final List<Pair<Long, Double>> loadOverTime = Collections
            .synchronizedList(new MaxList<Double>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Double>> ingestRateOverTime = Collections
            .synchronizedList(new MaxList<Double>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Double>> ingestByteRateOverTime = Collections
            .synchronizedList(new MaxList<Double>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Integer>> recoveriesOverTime = Collections
            .synchronizedList(new MaxList<Integer>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Integer>> minorCompactionsOverTime = Collections
            .synchronizedList(new MaxList<Integer>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Integer>> majorCompactionsOverTime = Collections
            .synchronizedList(new MaxList<Integer>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Double>> lookupsOverTime = Collections
            .synchronizedList(new MaxList<Double>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Integer>> queryRateOverTime = Collections
            .synchronizedList(new MaxList<Integer>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Integer>> scanRateOverTime = Collections
            .synchronizedList(new MaxList<Integer>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Double>> queryByteRateOverTime = Collections
            .synchronizedList(new MaxList<Double>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Double>> indexCacheHitRateOverTime = Collections
            .synchronizedList(new MaxList<Double>(MAX_TIME_PERIOD));
    private static final List<Pair<Long, Double>> dataCacheHitRateOverTime = Collections
            .synchronizedList(new MaxList<Double>(MAX_TIME_PERIOD));
    private static EventCounter lookupRateTracker = new EventCounter();
    private static EventCounter indexCacheHitTracker = new EventCounter();
    private static EventCounter indexCacheRequestTracker = new EventCounter();
    private static EventCounter dataCacheHitTracker = new EventCounter();
    private static EventCounter dataCacheRequestTracker = new EventCounter();

    private static volatile boolean fetching = false;
    private static MasterMonitorInfo mmi;
    private static Map<String, Map<ProblemType, Integer>> problemSummary = Collections.emptyMap();
    private static Exception problemException;
    private static GCStatus gcStatus;

    private static Instance instance;

    private static ServerConfiguration config;

    private static EmbeddedWebServer server;

    public static Map<String, Double> summarizeTableStats(MasterMonitorInfo mmi) {
        Map<String, Double> compactingByTable = new HashMap<String, Double>();
        if (mmi != null && mmi.tServerInfo != null) {
            for (TabletServerStatus status : mmi.tServerInfo) {
                if (status != null && status.tableMap != null) {
                    for (String table : status.tableMap.keySet()) {
                        Double holdTime = compactingByTable.get(table);
                        compactingByTable.put(table,
                                Math.max(holdTime == null ? 0. : holdTime.doubleValue(), status.holdTime));
                    }
                }
            }
        }
        return compactingByTable;
    }

    public static void add(TableInfo total, TableInfo more) {
        if (total.minors == null)
            total.minors = new Compacting();
        if (total.majors == null)
            total.majors = new Compacting();
        if (total.scans == null)
            total.scans = new Compacting();
        if (more.minors != null) {
            total.minors.running += more.minors.running;
            total.minors.queued += more.minors.queued;
        }
        if (more.majors != null) {
            total.majors.running += more.majors.running;
            total.majors.queued += more.majors.queued;
        }
        if (more.scans != null) {
            total.scans.running += more.scans.running;
            total.scans.queued += more.scans.queued;
        }
        total.onlineTablets += more.onlineTablets;
        total.recs += more.recs;
        total.recsInMemory += more.recsInMemory;
        total.tablets += more.tablets;
        total.ingestRate += more.ingestRate;
        total.ingestByteRate += more.ingestByteRate;
        total.queryRate += more.queryRate;
        total.queryByteRate += more.queryByteRate;
        total.scanRate += more.scanRate;
    }

    public static TableInfo summarizeTableStats(TabletServerStatus status) {
        TableInfo summary = new TableInfo();
        summary.majors = new Compacting();
        summary.minors = new Compacting();
        summary.scans = new Compacting();
        for (TableInfo rates : status.tableMap.values()) {
            add(summary, rates);
        }
        return summary;
    }

    private static class EventCounter {

        Map<String, Pair<Long, Long>> prevSamples = new HashMap<String, Pair<Long, Long>>();
        Map<String, Pair<Long, Long>> samples = new HashMap<String, Pair<Long, Long>>();
        Set<String> serversUpdated = new HashSet<String>();

        void startingUpdates() {
            serversUpdated.clear();
        }

        void updateTabletServer(String name, long sampleTime, long numEvents) {
            Pair<Long, Long> newSample = new Pair<Long, Long>(sampleTime, numEvents);
            Pair<Long, Long> lastSample = samples.get(name);

            if (lastSample == null || !lastSample.equals(newSample)) {
                samples.put(name, newSample);
                if (lastSample != null) {
                    prevSamples.put(name, lastSample);
                }
            }
            serversUpdated.add(name);
        }

        void finishedUpdating() {
            // remove any tablet servers not updated
            samples.keySet().retainAll(serversUpdated);
            prevSamples.keySet().retainAll(serversUpdated);
        }

        double calculateRate() {
            double totalRate = 0;

            for (Entry<String, Pair<Long, Long>> entry : prevSamples.entrySet()) {
                Pair<Long, Long> prevSample = entry.getValue();
                Pair<Long, Long> sample = samples.get(entry.getKey());

                totalRate += (sample.getSecond() - prevSample.getSecond())
                        / ((sample.getFirst() - prevSample.getFirst()) / (double) 1000);
            }

            return totalRate;
        }

        long calculateCount() {
            long count = 0;

            for (Entry<String, Pair<Long, Long>> entry : prevSamples.entrySet()) {
                Pair<Long, Long> prevSample = entry.getValue();
                Pair<Long, Long> sample = samples.get(entry.getKey());

                count += sample.getSecond() - prevSample.getSecond();
            }

            return count;
        }
    }

    public static void fetchData() {
        double totalIngestRate = 0.;
        double totalIngestByteRate = 0.;
        double totalQueryRate = 0.;
        double totalQueryByteRate = 0.;
        double totalScanRate = 0.;
        long totalEntries = 0;
        int totalTabletCount = 0;
        int onlineTabletCount = 0;
        long totalHoldTime = 0;
        long totalLookups = 0;
        boolean retry = true;

        // only recalc every so often
        long currentTime = System.currentTimeMillis();
        if (currentTime - lastRecalc < REFRESH_TIME * 1000)
            return;

        synchronized (Monitor.class) {
            if (fetching)
                return;
            fetching = true;
        }

        try {
            while (retry) {
                MasterClientService.Iface client = null;
                try {
                    client = MasterClient.getConnection(HdfsZooInstance.getInstance());
                    if (client != null) {
                        mmi = client.getMasterStats(Tracer.traceInfo(),
                                SystemCredentials.get().toThrift(HdfsZooInstance.getInstance()));
                        retry = false;
                    } else {
                        mmi = null;
                    }
                    Monitor.gcStatus = fetchGcStatus();
                } catch (Exception e) {
                    mmi = null;
                    log.info("Error fetching stats: " + e);
                } finally {
                    if (client != null) {
                        MasterClient.close(client);
                    }
                }
                if (mmi == null)
                    UtilWaitThread.sleep(1000);
            }
            if (mmi != null) {
                int majorCompactions = 0;
                int minorCompactions = 0;

                lookupRateTracker.startingUpdates();
                indexCacheHitTracker.startingUpdates();
                indexCacheRequestTracker.startingUpdates();
                dataCacheHitTracker.startingUpdates();
                dataCacheRequestTracker.startingUpdates();

                for (TabletServerStatus server : mmi.tServerInfo) {
                    TableInfo summary = Monitor.summarizeTableStats(server);
                    totalIngestRate += summary.ingestRate;
                    totalIngestByteRate += summary.ingestByteRate;
                    totalQueryRate += summary.queryRate;
                    totalScanRate += summary.scanRate;
                    totalQueryByteRate += summary.queryByteRate;
                    totalEntries += summary.recs;
                    totalHoldTime += server.holdTime;
                    totalLookups += server.lookups;
                    majorCompactions += summary.majors.running;
                    minorCompactions += summary.minors.running;
                    lookupRateTracker.updateTabletServer(server.name, server.lastContact, server.lookups);
                    indexCacheHitTracker.updateTabletServer(server.name, server.lastContact, server.indexCacheHits);
                    indexCacheRequestTracker.updateTabletServer(server.name, server.lastContact,
                            server.indexCacheRequest);
                    dataCacheHitTracker.updateTabletServer(server.name, server.lastContact, server.dataCacheHits);
                    dataCacheRequestTracker.updateTabletServer(server.name, server.lastContact,
                            server.dataCacheRequest);
                }

                lookupRateTracker.finishedUpdating();
                indexCacheHitTracker.finishedUpdating();
                indexCacheRequestTracker.finishedUpdating();
                dataCacheHitTracker.finishedUpdating();
                dataCacheRequestTracker.finishedUpdating();

                int totalTables = 0;
                for (TableInfo tInfo : mmi.tableMap.values()) {
                    totalTabletCount += tInfo.tablets;
                    onlineTabletCount += tInfo.onlineTablets;
                    totalTables++;
                }
                Monitor.totalIngestRate = totalIngestRate;
                Monitor.totalTables = totalTables;
                totalIngestByteRate = totalIngestByteRate / 1000000.0;
                Monitor.totalIngestByteRate = totalIngestByteRate;
                Monitor.totalQueryRate = totalQueryRate;
                Monitor.totalScanRate = totalScanRate;
                totalQueryByteRate = totalQueryByteRate / 1000000.0;
                Monitor.totalQueryByteRate = totalQueryByteRate;
                Monitor.totalEntries = totalEntries;
                Monitor.totalTabletCount = totalTabletCount;
                Monitor.onlineTabletCount = onlineTabletCount;
                Monitor.totalHoldTime = totalHoldTime;
                Monitor.totalLookups = totalLookups;

                ingestRateOverTime.add(new Pair<Long, Double>(currentTime, totalIngestRate));
                ingestByteRateOverTime.add(new Pair<Long, Double>(currentTime, totalIngestByteRate));

                double totalLoad = 0.;
                for (TabletServerStatus status : mmi.tServerInfo) {
                    if (status != null)
                        totalLoad += status.osLoad;
                }
                loadOverTime.add(new Pair<Long, Double>(currentTime, totalLoad));

                minorCompactionsOverTime.add(new Pair<Long, Integer>(currentTime, minorCompactions));
                majorCompactionsOverTime.add(new Pair<Long, Integer>(currentTime, majorCompactions));

                lookupsOverTime.add(new Pair<Long, Double>(currentTime, lookupRateTracker.calculateRate()));

                queryRateOverTime.add(new Pair<Long, Integer>(currentTime, (int) totalQueryRate));
                queryByteRateOverTime.add(new Pair<Long, Double>(currentTime, totalQueryByteRate));

                scanRateOverTime.add(new Pair<Long, Integer>(currentTime, (int) totalScanRate));

                calcCacheHitRate(indexCacheHitRateOverTime, currentTime, indexCacheHitTracker,
                        indexCacheRequestTracker);
                calcCacheHitRate(dataCacheHitRateOverTime, currentTime, dataCacheHitTracker,
                        dataCacheRequestTracker);
            }
            try {
                Monitor.problemSummary = ProblemReports.getInstance().summarize();
                Monitor.problemException = null;
            } catch (Exception e) {
                log.info("Failed to obtain problem reports ", e);
                Monitor.problemSummary = Collections.emptyMap();
                Monitor.problemException = e;
            }

        } finally {
            synchronized (Monitor.class) {
                fetching = false;
                lastRecalc = currentTime;
            }
        }
    }

    private static void calcCacheHitRate(List<Pair<Long, Double>> hitRate, long currentTime, EventCounter cacheHits,
            EventCounter cacheReq) {
        long req = cacheReq.calculateCount();
        if (req > 0)
            hitRate.add(new Pair<Long, Double>(currentTime,
                    cacheHits.calculateCount() / (double) cacheReq.calculateCount()));
        else
            hitRate.add(new Pair<Long, Double>(currentTime, null));
    }

    private static GCStatus fetchGcStatus() {
        GCStatus result = null;
        HostAndPort address = null;
        try {
            // Read the gc location from its lock
            Instance instance = HdfsZooInstance.getInstance();
            String zooKeepers = instance.getZooKeepers();
            log.debug("connecting to zookeepers " + zooKeepers);
            ZooKeeper zk = new ZooKeeper(zooKeepers,
                    (int) config.getConfiguration().getTimeInMillis(Property.INSTANCE_ZK_TIMEOUT), new Watcher() {
                        @Override
                        public void process(WatchedEvent event) {
                        }
                    });
            try {
                String path = ZooUtil.getRoot(HdfsZooInstance.getInstance()) + Constants.ZGC_LOCK;
                List<String> locks = zk.getChildren(path, null);
                if (locks != null && locks.size() > 0) {
                    Collections.sort(locks);
                    address = new ServerServices(new String(zk.getData(path + "/" + locks.get(0), null, null)))
                            .getAddress(Service.GC_CLIENT);
                    GCMonitorService.Client client = ThriftUtil.getClient(new GCMonitorService.Client.Factory(),
                            address, config.getConfiguration());
                    try {
                        result = client.getStatus(Tracer.traceInfo(), SystemCredentials.get().toThrift(instance));
                    } finally {
                        ThriftUtil.returnClient(client);
                    }
                }
            } finally {
                zk.close();
            }
        } catch (Exception ex) {
            log.warn("Unable to contact the garbage collector at " + address, ex);
        }
        return result;
    }

    public static void main(String[] args) throws Exception {
        SecurityUtil.serverLogin();

        VolumeManager fs = VolumeManagerImpl.get();
        ServerOpts opts = new ServerOpts();
        opts.parseArgs("monitor", args);
        String hostname = opts.getAddress();
        instance = HdfsZooInstance.getInstance();
        config = new ServerConfiguration(instance);
        Accumulo.init(fs, config, "monitor");
        Monitor monitor = new Monitor();
        Accumulo.enableTracing(hostname, "monitor");
        monitor.run(hostname);
    }

    private static long START_TIME;

    public void run(String hostname) {
        Monitor.START_TIME = System.currentTimeMillis();
        int port = config.getConfiguration().getPort(Property.MONITOR_PORT);
        try {
            log.debug("Creating monitor on port " + port);
            server = new EmbeddedWebServer(hostname, port);
        } catch (Throwable ex) {
            log.error("Unable to start embedded web server", ex);
            throw new RuntimeException(ex);
        }

        server.addServlet(DefaultServlet.class, "/");
        server.addServlet(OperationServlet.class, "/op");
        server.addServlet(MasterServlet.class, "/master");
        server.addServlet(TablesServlet.class, "/tables");
        server.addServlet(TServersServlet.class, "/tservers");
        server.addServlet(ProblemServlet.class, "/problems");
        server.addServlet(GcStatusServlet.class, "/gc");
        server.addServlet(LogServlet.class, "/log");
        server.addServlet(XMLServlet.class, "/xml");
        server.addServlet(JSONServlet.class, "/json");
        server.addServlet(VisServlet.class, "/vis");
        server.addServlet(Summary.class, "/trace/summary");
        server.addServlet(ListType.class, "/trace/listType");
        server.addServlet(ShowTrace.class, "/trace/show");
        if (server.isUsingSsl())
            server.addServlet(ShellServlet.class, "/shell");
        server.start();

        try {
            String monitorAddress = HostAndPort.fromParts(hostname, server.getPort()).toString();
            ZooReaderWriter.getInstance().putPersistentData(ZooUtil.getRoot(instance) + Constants.ZMONITOR,
                    monitorAddress.getBytes(), NodeExistsPolicy.OVERWRITE);
            log.info("Set monitor address in zookeeper to " + monitorAddress);
        } catch (Exception ex) {
            log.error("Unable to set monitor address in zookeeper");
        }
        LogService.startLogListener(Monitor.getSystemConfiguration(), instance.getInstanceID());

        new Daemon(new LoggingRunnable(log, new ZooKeeperStatus()), "ZooKeeperStatus").start();

        // need to regularly fetch data so plot data is updated
        new Daemon(new LoggingRunnable(log, new Runnable() {

            @Override
            public void run() {
                while (true) {
                    try {
                        Monitor.fetchData();
                    } catch (Exception e) {
                        log.warn(e.getMessage(), e);
                    }

                    UtilWaitThread.sleep(333);
                }

            }
        }), "Data fetcher").start();
    }

    public static MasterMonitorInfo getMmi() {
        return mmi;
    }

    public static int getTotalTables() {
        return totalTables;
    }

    public static int getTotalTabletCount() {
        return totalTabletCount;
    }

    public static int getOnlineTabletCount() {
        return onlineTabletCount;
    }

    public static long getTotalEntries() {
        return totalEntries;
    }

    public static double getTotalIngestRate() {
        return totalIngestRate;
    }

    public static double getTotalIngestByteRate() {
        return totalIngestByteRate;
    }

    public static double getTotalQueryRate() {
        return totalQueryRate;
    }

    public static double getTotalScanRate() {
        return totalScanRate;
    }

    public static double getTotalQueryByteRate() {
        return totalQueryByteRate;
    }

    public static long getTotalHoldTime() {
        return totalHoldTime;
    }

    public static Exception getProblemException() {
        return problemException;
    }

    public static Map<String, Map<ProblemType, Integer>> getProblemSummary() {
        return problemSummary;
    }

    public static GCStatus getGcStatus() {
        return gcStatus;
    }

    public static long getTotalLookups() {
        return totalLookups;
    }

    public static long getStartTime() {
        return START_TIME;
    }

    public static List<Pair<Long, Double>> getLoadOverTime() {
        synchronized (loadOverTime) {
            return new ArrayList<Pair<Long, Double>>(loadOverTime);
        }
    }

    public static List<Pair<Long, Double>> getIngestRateOverTime() {
        synchronized (ingestRateOverTime) {
            return new ArrayList<Pair<Long, Double>>(ingestRateOverTime);
        }
    }

    public static List<Pair<Long, Double>> getIngestByteRateOverTime() {
        synchronized (ingestByteRateOverTime) {
            return new ArrayList<Pair<Long, Double>>(ingestByteRateOverTime);
        }
    }

    public static List<Pair<Long, Integer>> getRecoveriesOverTime() {
        synchronized (recoveriesOverTime) {
            return new ArrayList<Pair<Long, Integer>>(recoveriesOverTime);
        }
    }

    public static List<Pair<Long, Integer>> getMinorCompactionsOverTime() {
        synchronized (minorCompactionsOverTime) {
            return new ArrayList<Pair<Long, Integer>>(minorCompactionsOverTime);
        }
    }

    public static List<Pair<Long, Integer>> getMajorCompactionsOverTime() {
        synchronized (majorCompactionsOverTime) {
            return new ArrayList<Pair<Long, Integer>>(majorCompactionsOverTime);
        }
    }

    public static List<Pair<Long, Double>> getLookupsOverTime() {
        synchronized (lookupsOverTime) {
            return new ArrayList<Pair<Long, Double>>(lookupsOverTime);
        }
    }

    public static double getLookupRate() {
        return lookupRateTracker.calculateRate();
    }

    public static List<Pair<Long, Integer>> getQueryRateOverTime() {
        synchronized (queryRateOverTime) {
            return new ArrayList<Pair<Long, Integer>>(queryRateOverTime);
        }
    }

    public static List<Pair<Long, Integer>> getScanRateOverTime() {
        synchronized (scanRateOverTime) {
            return new ArrayList<Pair<Long, Integer>>(scanRateOverTime);
        }
    }

    public static List<Pair<Long, Double>> getQueryByteRateOverTime() {
        synchronized (queryByteRateOverTime) {
            return new ArrayList<Pair<Long, Double>>(queryByteRateOverTime);
        }
    }

    public static List<Pair<Long, Double>> getIndexCacheHitRateOverTime() {
        synchronized (indexCacheHitRateOverTime) {
            return new ArrayList<Pair<Long, Double>>(indexCacheHitRateOverTime);
        }
    }

    public static List<Pair<Long, Double>> getDataCacheHitRateOverTime() {
        synchronized (dataCacheHitRateOverTime) {
            return new ArrayList<Pair<Long, Double>>(dataCacheHitRateOverTime);
        }
    }

    public static AccumuloConfiguration getSystemConfiguration() {
        return config.getConfiguration();
    }

    public static Instance getInstance() {
        return instance;
    }

    public static boolean isUsingSsl() {
        return server.isUsingSsl();
    }
}