Examples with Throttler com.github.ambry.utils.Throttler used on opensource projects

Example 1 with Throttler

use of com.github.ambry.utils.Throttler in project ambry by linkedin.

the class ConsistencyCheckerTool method main.

public static void main(String[] args) throws Exception {
    VerifiableProperties properties = ToolUtils.getVerifiableProperties(args);
    ConsistencyCheckerToolConfig config = new ConsistencyCheckerToolConfig(properties);
    ClusterMapConfig clusterMapConfig = new ClusterMapConfig(properties);
    ServerConfig serverConfig = new ServerConfig(properties);
    try (ClusterMap clusterMap = new StaticClusterAgentsFactory(clusterMapConfig, config.hardwareLayoutFilePath, config.partitionLayoutFilePath).getClusterMap()) {
        StoreToolsMetrics metrics = new StoreToolsMetrics(clusterMap.getMetricRegistry());
        StoreConfig storeConfig = new StoreConfig(properties);
        // this tool supports only blob IDs. It can become generic if StoreKeyFactory provides a deserFromString method.
        BlobIdFactory blobIdFactory = new BlobIdFactory(clusterMap);
        Set<StoreKey> filterKeySet = new HashSet<>();
        for (String key : config.filterSet) {
            filterKeySet.add(new BlobId(key, clusterMap));
        }
        Time time = SystemTime.getInstance();
        Throttler throttler = new Throttler(config.indexEntriesToProcessPerSec, 1000, true, time);
        StoreKeyConverterFactory storeKeyConverterFactory = Utils.getObj(serverConfig.serverStoreKeyConverterFactory, properties, clusterMap.getMetricRegistry());
        ConsistencyCheckerTool consistencyCheckerTool = new ConsistencyCheckerTool(clusterMap, blobIdFactory, storeConfig, filterKeySet, throttler, metrics, time, storeKeyConverterFactory.getStoreKeyConverter());
        boolean success = consistencyCheckerTool.checkConsistency(config.pathOfInput.listFiles(File::isDirectory)).getFirst();
        System.exit(success ? 0 : 1);
    }
}

Example 2 with Throttler

use of com.github.ambry.utils.Throttler in project ambry by linkedin.

the class ServerReadPerformance method main.

public static void main(String[] args) {
    ConnectionPool connectionPool = null;
    FileWriter writer = null;
    try {
        OptionParser parser = new OptionParser();
        ArgumentAcceptingOptionSpec<String> logToReadOpt = parser.accepts("logToRead", "The log that needs to be replayed for traffic").withRequiredArg().describedAs("log_to_read").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> hardwareLayoutOpt = parser.accepts("hardwareLayout", "The path of the hardware layout file").withRequiredArg().describedAs("hardware_layout").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> partitionLayoutOpt = parser.accepts("partitionLayout", "The path of the partition layout file").withRequiredArg().describedAs("partition_layout").ofType(String.class);
        ArgumentAcceptingOptionSpec<Integer> readsPerSecondOpt = parser.accepts("readsPerSecond", "The rate at which reads need to be performed").withRequiredArg().describedAs("The number of reads per second").ofType(Integer.class).defaultsTo(1000);
        ArgumentAcceptingOptionSpec<Long> measurementIntervalOpt = parser.accepts("measurementInterval", "The interval in second to report performance result").withOptionalArg().describedAs("The CPU time spent for getting blobs, not wall time").ofType(Long.class).defaultsTo(300L);
        ArgumentAcceptingOptionSpec<Boolean> verboseLoggingOpt = parser.accepts("enableVerboseLogging", "Enables verbose logging").withOptionalArg().describedAs("Enable verbose logging").ofType(Boolean.class).defaultsTo(false);
        ArgumentAcceptingOptionSpec<String> sslEnabledDatacentersOpt = parser.accepts("sslEnabledDatacenters", "Datacenters to which ssl should be enabled").withOptionalArg().describedAs("Comma separated list").ofType(String.class).defaultsTo("");
        ArgumentAcceptingOptionSpec<String> sslKeystorePathOpt = parser.accepts("sslKeystorePath", "SSL key store path").withOptionalArg().describedAs("The file path of SSL key store").defaultsTo("").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> sslKeystoreTypeOpt = parser.accepts("sslKeystoreType", "SSL key store type").withOptionalArg().describedAs("The type of SSL key store").defaultsTo("").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> sslTruststorePathOpt = parser.accepts("sslTruststorePath", "SSL trust store path").withOptionalArg().describedAs("The file path of SSL trust store").defaultsTo("").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> sslKeystorePasswordOpt = parser.accepts("sslKeystorePassword", "SSL key store password").withOptionalArg().describedAs("The password of SSL key store").defaultsTo("").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> sslKeyPasswordOpt = parser.accepts("sslKeyPassword", "SSL key password").withOptionalArg().describedAs("The password of SSL private key").defaultsTo("").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> sslTruststorePasswordOpt = parser.accepts("sslTruststorePassword", "SSL trust store password").withOptionalArg().describedAs("The password of SSL trust store").defaultsTo("").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> sslCipherSuitesOpt = parser.accepts("sslCipherSuites", "SSL enabled cipher suites").withOptionalArg().describedAs("Comma separated list").defaultsTo("TLS_RSA_WITH_AES_128_CBC_SHA").ofType(String.class);
        OptionSet options = parser.parse(args);
        ArrayList<OptionSpec> listOpt = new ArrayList<>();
        listOpt.add(logToReadOpt);
        listOpt.add(hardwareLayoutOpt);
        listOpt.add(partitionLayoutOpt);
        ToolUtils.ensureOrExit(listOpt, options, parser);
        long measurementIntervalNs = options.valueOf(measurementIntervalOpt) * SystemTime.NsPerSec;
        ToolUtils.validateSSLOptions(options, parser, sslEnabledDatacentersOpt, sslKeystorePathOpt, sslKeystoreTypeOpt, sslTruststorePathOpt, sslKeystorePasswordOpt, sslKeyPasswordOpt, sslTruststorePasswordOpt);
        String sslEnabledDatacenters = options.valueOf(sslEnabledDatacentersOpt);
        Properties sslProperties;
        if (sslEnabledDatacenters.length() != 0) {
            sslProperties = ToolUtils.createSSLProperties(sslEnabledDatacenters, options.valueOf(sslKeystorePathOpt), options.valueOf(sslKeystoreTypeOpt), options.valueOf(sslKeystorePasswordOpt), options.valueOf(sslKeyPasswordOpt), options.valueOf(sslTruststorePathOpt), options.valueOf(sslTruststorePasswordOpt), options.valueOf(sslCipherSuitesOpt));
        } else {
            sslProperties = new Properties();
        }
        ToolUtils.addClusterMapProperties(sslProperties);
        String logToRead = options.valueOf(logToReadOpt);
        int readsPerSecond = options.valueOf(readsPerSecondOpt);
        boolean enableVerboseLogging = options.has(verboseLoggingOpt);
        if (enableVerboseLogging) {
            System.out.println("Enabled verbose logging");
        }
        File logFile = new File(System.getProperty("user.dir"), "readperfresult");
        writer = new FileWriter(logFile);
        String hardwareLayoutPath = options.valueOf(hardwareLayoutOpt);
        String partitionLayoutPath = options.valueOf(partitionLayoutOpt);
        ClusterMapConfig clusterMapConfig = new ClusterMapConfig(new VerifiableProperties(sslProperties));
        ClusterMap map = ((ClusterAgentsFactory) Utils.getObj(clusterMapConfig.clusterMapClusterAgentsFactory, clusterMapConfig, hardwareLayoutPath, partitionLayoutPath)).getClusterMap();
        final AtomicLong totalTimeTaken = new AtomicLong(0);
        final AtomicLong totalReads = new AtomicLong(0);
        final AtomicBoolean shutdown = new AtomicBoolean(false);
        // attach shutdown handler to catch control-c
        Runtime.getRuntime().addShutdownHook(new Thread() {

            public void run() {
                try {
                    System.out.println("Shutdown invoked");
                    shutdown.set(true);
                    String message = "Total reads : " + totalReads.get() + "  Total time taken : " + totalTimeTaken.get() + " Nano Seconds  Average time taken per read " + ((double) totalTimeTaken.get()) / SystemTime.NsPerSec / totalReads.get() + " Seconds";
                    System.out.println(message);
                } catch (Exception e) {
                    System.out.println("Error while shutting down " + e);
                }
            }
        });
        final BufferedReader br = new BufferedReader(new FileReader(logToRead));
        Throttler throttler = new Throttler(readsPerSecond, 100, true, SystemTime.getInstance());
        String line;
        ConnectedChannel channel = null;
        ConnectionPoolConfig connectionPoolConfig = new ConnectionPoolConfig(new VerifiableProperties(new Properties()));
        VerifiableProperties vProps = new VerifiableProperties(sslProperties);
        SSLConfig sslConfig = new SSLConfig(vProps);
        clusterMapConfig = new ClusterMapConfig(vProps);
        connectionPool = new BlockingChannelConnectionPool(connectionPoolConfig, sslConfig, clusterMapConfig, new MetricRegistry());
        long totalNumberOfGetBlobs = 0;
        long totalLatencyForGetBlobs = 0;
        ArrayList<Long> latenciesForGetBlobs = new ArrayList<Long>();
        long maxLatencyForGetBlobs = 0;
        long minLatencyForGetBlobs = Long.MAX_VALUE;
        while ((line = br.readLine()) != null) {
            String[] id = line.split("-");
            BlobData blobData = null;
            BlobId blobId = new BlobId(id[1], map);
            ArrayList<BlobId> blobIds = new ArrayList<BlobId>();
            blobIds.add(blobId);
            for (ReplicaId replicaId : blobId.getPartition().getReplicaIds()) {
                long startTimeGetBlob = 0;
                ArrayList<PartitionRequestInfo> partitionRequestInfoList = new ArrayList<PartitionRequestInfo>();
                try {
                    partitionRequestInfoList.clear();
                    PartitionRequestInfo partitionRequestInfo = new PartitionRequestInfo(blobId.getPartition(), blobIds);
                    partitionRequestInfoList.add(partitionRequestInfo);
                    GetRequest getRequest = new GetRequest(1, "getperf", MessageFormatFlags.Blob, partitionRequestInfoList, GetOption.None);
                    Port port = replicaId.getDataNodeId().getPortToConnectTo();
                    channel = connectionPool.checkOutConnection(replicaId.getDataNodeId().getHostname(), port, 10000);
                    startTimeGetBlob = SystemTime.getInstance().nanoseconds();
                    channel.send(getRequest);
                    DataInputStream receiveStream = channel.receive().getInputStream();
                    GetResponse getResponse = GetResponse.readFrom(receiveStream, map);
                    blobData = MessageFormatRecord.deserializeBlob(getResponse.getInputStream());
                    long sizeRead = 0;
                    byte[] outputBuffer = new byte[(int) blobData.getSize()];
                    ByteBufferOutputStream streamOut = new ByteBufferOutputStream(ByteBuffer.wrap(outputBuffer));
                    ByteBuf buffer = blobData.content();
                    try {
                        buffer.readBytes(streamOut, (int) blobData.getSize());
                    } finally {
                        buffer.release();
                    }
                    long latencyPerBlob = SystemTime.getInstance().nanoseconds() - startTimeGetBlob;
                    totalTimeTaken.addAndGet(latencyPerBlob);
                    latenciesForGetBlobs.add(latencyPerBlob);
                    totalReads.incrementAndGet();
                    totalNumberOfGetBlobs++;
                    totalLatencyForGetBlobs += latencyPerBlob;
                    if (enableVerboseLogging) {
                        System.out.println("Time taken to get blob id " + blobId + " in ms " + latencyPerBlob / SystemTime.NsPerMs);
                    }
                    if (latencyPerBlob > maxLatencyForGetBlobs) {
                        maxLatencyForGetBlobs = latencyPerBlob;
                    }
                    if (latencyPerBlob < minLatencyForGetBlobs) {
                        minLatencyForGetBlobs = latencyPerBlob;
                    }
                    if (totalLatencyForGetBlobs >= measurementIntervalNs) {
                        Collections.sort(latenciesForGetBlobs);
                        int index99 = (int) (latenciesForGetBlobs.size() * 0.99) - 1;
                        int index95 = (int) (latenciesForGetBlobs.size() * 0.95) - 1;
                        String message = totalNumberOfGetBlobs + "," + (double) latenciesForGetBlobs.get(index99) / SystemTime.NsPerSec + "," + (double) latenciesForGetBlobs.get(index95) / SystemTime.NsPerSec + "," + ((double) totalLatencyForGetBlobs / SystemTime.NsPerSec / totalNumberOfGetBlobs);
                        System.out.println(message);
                        writer.write(message + "\n");
                        totalLatencyForGetBlobs = 0;
                        latenciesForGetBlobs.clear();
                        totalNumberOfGetBlobs = 0;
                        maxLatencyForGetBlobs = 0;
                        minLatencyForGetBlobs = Long.MAX_VALUE;
                    }
                    partitionRequestInfoList.clear();
                    partitionRequestInfo = new PartitionRequestInfo(blobId.getPartition(), blobIds);
                    partitionRequestInfoList.add(partitionRequestInfo);
                    GetRequest getRequestProperties = new GetRequest(1, "getperf", MessageFormatFlags.BlobProperties, partitionRequestInfoList, GetOption.None);
                    long startTimeGetBlobProperties = SystemTime.getInstance().nanoseconds();
                    channel.send(getRequestProperties);
                    DataInputStream receivePropertyStream = channel.receive().getInputStream();
                    GetResponse getResponseProperty = GetResponse.readFrom(receivePropertyStream, map);
                    BlobProperties blobProperties = MessageFormatRecord.deserializeBlobProperties(getResponseProperty.getInputStream());
                    long endTimeGetBlobProperties = SystemTime.getInstance().nanoseconds() - startTimeGetBlobProperties;
                    partitionRequestInfoList.clear();
                    partitionRequestInfo = new PartitionRequestInfo(blobId.getPartition(), blobIds);
                    partitionRequestInfoList.add(partitionRequestInfo);
                    GetRequest getRequestUserMetadata = new GetRequest(1, "getperf", MessageFormatFlags.BlobUserMetadata, partitionRequestInfoList, GetOption.None);
                    long startTimeGetBlobUserMetadata = SystemTime.getInstance().nanoseconds();
                    channel.send(getRequestUserMetadata);
                    DataInputStream receiveUserMetadataStream = channel.receive().getInputStream();
                    GetResponse getResponseUserMetadata = GetResponse.readFrom(receiveUserMetadataStream, map);
                    ByteBuffer userMetadata = MessageFormatRecord.deserializeUserMetadata(getResponseUserMetadata.getInputStream());
                    long endTimeGetBlobUserMetadata = SystemTime.getInstance().nanoseconds() - startTimeGetBlobUserMetadata;
                    // delete the blob
                    DeleteRequest deleteRequest = new DeleteRequest(0, "perf", blobId, System.currentTimeMillis());
                    channel.send(deleteRequest);
                    DeleteResponse deleteResponse = DeleteResponse.readFrom(channel.receive().getInputStream());
                    if (deleteResponse.getError() != ServerErrorCode.No_Error) {
                        throw new UnexpectedException("error " + deleteResponse.getError());
                    }
                    throttler.maybeThrottle(1);
                } finally {
                    if (channel != null) {
                        connectionPool.checkInConnection(channel);
                        channel = null;
                    }
                }
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
        System.out.println("Error in server read performance " + e);
    } finally {
        if (writer != null) {
            try {
                writer.close();
            } catch (Exception e) {
                System.out.println("Error when closing writer");
            }
        }
        if (connectionPool != null) {
            connectionPool.shutdown();
        }
    }
}

Example 3 with Throttler

use of com.github.ambry.utils.Throttler in project ambry by linkedin.

the class IndexWritePerformance method main.

public static void main(String[] args) {
    FileWriter writer = null;
    try {
        OptionParser parser = new OptionParser();
        ArgumentAcceptingOptionSpec<Integer> numberOfIndexesOpt = parser.accepts("numberOfIndexes", "The number of indexes to create").withRequiredArg().describedAs("number_of_indexes").ofType(Integer.class);
        ArgumentAcceptingOptionSpec<String> hardwareLayoutOpt = parser.accepts("hardwareLayout", "The path of the hardware layout file").withRequiredArg().describedAs("hardware_layout").ofType(String.class);
        ArgumentAcceptingOptionSpec<String> partitionLayoutOpt = parser.accepts("partitionLayout", "The path of the partition layout file").withRequiredArg().describedAs("partition_layout").ofType(String.class);
        ArgumentAcceptingOptionSpec<Integer> numberOfWritersOpt = parser.accepts("numberOfWriters", "The number of writers that write to a random index concurrently").withRequiredArg().describedAs("The number of writers").ofType(Integer.class).defaultsTo(4);
        ArgumentAcceptingOptionSpec<Integer> writesPerSecondOpt = parser.accepts("writesPerSecond", "The rate at which writes need to be performed").withRequiredArg().describedAs("The number of writes per second").ofType(Integer.class).defaultsTo(1000);
        ArgumentAcceptingOptionSpec<Boolean> verboseLoggingOpt = parser.accepts("enableVerboseLogging", "Enables verbose logging").withOptionalArg().describedAs("Enable verbose logging").ofType(Boolean.class).defaultsTo(false);
        OptionSet options = parser.parse(args);
        ArrayList<OptionSpec> listOpt = new ArrayList<>();
        listOpt.add(numberOfIndexesOpt);
        listOpt.add(hardwareLayoutOpt);
        listOpt.add(partitionLayoutOpt);
        ToolUtils.ensureOrExit(listOpt, options, parser);
        int numberOfIndexes = options.valueOf(numberOfIndexesOpt);
        int numberOfWriters = options.valueOf(numberOfWritersOpt);
        int writesPerSecond = options.valueOf(writesPerSecondOpt);
        boolean enableVerboseLogging = options.has(verboseLoggingOpt);
        if (enableVerboseLogging) {
            System.out.println("Enabled verbose logging");
        }
        final AtomicLong totalTimeTakenInNs = new AtomicLong(0);
        final AtomicLong totalWrites = new AtomicLong(0);
        String hardwareLayoutPath = options.valueOf(hardwareLayoutOpt);
        String partitionLayoutPath = options.valueOf(partitionLayoutOpt);
        ClusterMapConfig clusterMapConfig = new ClusterMapConfig(new VerifiableProperties(new Properties()));
        ClusterMap map = ((ClusterAgentsFactory) Utils.getObj(clusterMapConfig.clusterMapClusterAgentsFactory, clusterMapConfig, hardwareLayoutPath, partitionLayoutPath)).getClusterMap();
        StoreKeyFactory factory = new BlobIdFactory(map);
        File logFile = new File(System.getProperty("user.dir"), "writeperflog");
        writer = new FileWriter(logFile);
        MetricRegistry metricRegistry = new MetricRegistry();
        StoreMetrics metrics = new StoreMetrics(metricRegistry);
        DiskSpaceAllocator diskSpaceAllocator = new DiskSpaceAllocator(false, null, 0, new StorageManagerMetrics(metricRegistry));
        Properties props = new Properties();
        props.setProperty("store.index.memory.size.bytes", "2097152");
        props.setProperty("store.segment.size.in.bytes", "10");
        StoreConfig config = new StoreConfig(new VerifiableProperties(props));
        Log log = new Log(System.getProperty("user.dir"), 10, diskSpaceAllocator, config, metrics, null);
        ScheduledExecutorService s = Utils.newScheduler(numberOfWriters, "index", false);
        ArrayList<BlobIndexMetrics> indexWithMetrics = new ArrayList<BlobIndexMetrics>(numberOfIndexes);
        for (int i = 0; i < numberOfIndexes; i++) {
            File indexFile = new File(System.getProperty("user.dir"), Integer.toString(i));
            if (indexFile.exists()) {
                for (File c : indexFile.listFiles()) {
                    c.delete();
                }
            } else {
                indexFile.mkdir();
            }
            System.out.println("Creating index folder " + indexFile.getAbsolutePath());
            writer.write("logdir-" + indexFile.getAbsolutePath() + "\n");
            indexWithMetrics.add(new BlobIndexMetrics(indexFile.getAbsolutePath(), s, log, enableVerboseLogging, totalWrites, totalTimeTakenInNs, totalWrites, config, writer, factory));
        }
        final CountDownLatch latch = new CountDownLatch(numberOfWriters);
        final AtomicBoolean shutdown = new AtomicBoolean(false);
        // attach shutdown handler to catch control-c
        Runtime.getRuntime().addShutdownHook(new Thread() {

            public void run() {
                try {
                    System.out.println("Shutdown invoked");
                    shutdown.set(true);
                    latch.await();
                    System.out.println("Total writes : " + totalWrites.get() + "  Total time taken : " + totalTimeTakenInNs.get() + " Nano Seconds  Average time taken per write " + ((double) totalWrites.get() / totalTimeTakenInNs.get()) / SystemTime.NsPerSec + " Seconds");
                } catch (Exception e) {
                    System.out.println("Error while shutting down " + e);
                }
            }
        });
        Throttler throttler = new Throttler(writesPerSecond, 100, true, SystemTime.getInstance());
        Thread[] threadIndexPerf = new Thread[numberOfWriters];
        for (int i = 0; i < numberOfWriters; i++) {
            threadIndexPerf[i] = new Thread(new IndexWritePerfRun(indexWithMetrics, throttler, shutdown, latch, map));
            threadIndexPerf[i].start();
        }
        for (int i = 0; i < numberOfWriters; i++) {
            threadIndexPerf[i].join();
        }
    } catch (StoreException e) {
        System.err.println("Index creation error on exit " + e.getMessage());
    } catch (Exception e) {
        System.err.println("Error on exit " + e);
    } finally {
        if (writer != null) {
            try {
                writer.close();
            } catch (Exception e) {
                System.out.println("Error when closing the writer");
            }
        }
    }
}

Example 4 with Throttler

use of com.github.ambry.utils.Throttler in project ambry by linkedin.

the class DiskManager method getThrottlers.

/**
 * Gets all the throttlers that the {@link DiskIOScheduler} will be constructed with.
 * @param config the {@link StoreConfig} with configuration values.
 * @param time the {@link Time} instance to use in the throttlers
 * @return the throttlers that the {@link DiskIOScheduler} will be constructed with.
 */
private Map<String, Throttler> getThrottlers(StoreConfig config, Time time) {
    Map<String, Throttler> throttlers = new HashMap<>();
    // compaction ops
    Throttler compactionOpsThrottler = new Throttler(config.storeCompactionOperationsBytesPerSec, config.storeCompactionThrottlerCheckIntervalMs, true, time);
    throttlers.put(BlobStoreCompactor.COMPACTION_CLEANUP_JOB_NAME, compactionOpsThrottler);
    // hard delete ops
    Throttler hardDeleteOpsThrottler = new Throttler(config.storeHardDeleteOperationsBytesPerSec, -1, true, time);
    throttlers.put(HardDeleter.HARD_DELETE_CLEANUP_JOB_NAME, hardDeleteOpsThrottler);
    // stats
    Throttler statsIndexScanThrottler = new Throttler(config.storeStatsIndexEntriesPerSecond, 1000, true, time);
    throttlers.put(BlobStoreStats.IO_SCHEDULER_JOB_TYPE, statsIndexScanThrottler);
    return throttlers;
}

Example 5 with Throttler

use of com.github.ambry.utils.Throttler in project ambry by linkedin.

the class DiskIOSchedulerTest method basicTest.

/**
 * Test that the correct throttlers are used for different job types.
 * @throws Exception
 */
@Test
public void basicTest() throws Exception {
    final int numJobTypes = 5;
    Map<String, Throttler> throttlers = new HashMap<>();
    for (int i = 0; i < numJobTypes; i++) {
        String jobType = Integer.toString(i);
        throttlers.put(jobType, new MockThrottler());
    }
    DiskIOScheduler scheduler = new DiskIOScheduler(throttlers);
    // recognized job types
    for (int i = 0; i < numJobTypes; i++) {
        String jobType = Integer.toString(i);
        Long usedSinceLastCall = ThreadLocalRandom.current().nextLong(Long.MAX_VALUE);
        assertEquals("Unexpected i/o slice availability returned", Long.MAX_VALUE, scheduler.getSlice(jobType, "job", usedSinceLastCall));
        MockThrottler throttler = (MockThrottler) throttlers.get(jobType);
        assertTrue("maybeThrottle should have been called for this jobType", throttler.called);
        assertEquals("observed units passed to throttler not as expected", usedSinceLastCall, throttler.observedUnits, 0.0);
    }
    for (Throttler throttler : throttlers.values()) {
        ((MockThrottler) throttler).reset();
    }
    // unrecognized job type
    String jobType = Integer.toString(numJobTypes);
    assertEquals("Unexpected i/o slice availability returned", Long.MAX_VALUE, scheduler.getSlice(jobType, "job", 0));
    for (Throttler throttler : throttlers.values()) {
        assertFalse("maybeThrottle should not have been called for this jobType", ((MockThrottler) throttler).called);
    }
    // disabling scheduler
    scheduler.disable();
    for (Throttler throttler : throttlers.values()) {
        assertTrue("Throttler should be closed.", ((MockThrottler) throttler).closed);
    }
}