Examples of RateLimiter

com.google.common.util.concurrent.RateLimiter
kipedia.org/wiki/Little's_law">Little's Law).
A {@code RateLimiter} is defined primarily by the rate at which permitsare issued. Absent additional configuration, permits will be distributed at a fixed rate, defined in terms of permits per second. Permits will be distributed smoothly, with the delay between individual permits being adjusted to ensure that the configured rate is maintained.
It is possible to configure a {@code RateLimiter} to have a warmupperiod during which time the permits issued each second steadily increases until it hits the stable rate.
As an example, imagine that we have a list of tasks to execute, but we don't want to submit more than 2 per second:
```
   {@code final RateLimiter rateLimiter = RateLimiter.create(2.0); // rate is "2 permits per second"}void submitTasks(List tasks, Executor executor)  for (Runnable task : tasks) { rateLimiter.acquire(); // may wait executor.execute(task); } } }
```
As another example, imagine that we produce a stream of data, and we want to cap it at 5kb per second. This could be accomplished by requiring a permit per byte, and specifying a rate of 5000 permits per second:
```
   {@code final RateLimiter rateLimiter = RateLimiter.create(5000.0); // rate = 5000 permits per second}void submitPacket(byte[] packet)  rateLimiter.acquire(packet.length); networkService.send(packet); } }
```
It is important to note that the number of permits requested never affect the throttling of the request itself (an invocation to {@code acquire(1)}and an invocation to {@code acquire(1000)} will result in exactly the same throttling, if any),but it affects the throttling of the next request. I.e., if an expensive task arrives at an idle RateLimiter, it will be granted immediately, but it is the next request that will experience extra throttling, thus paying for the cost of the expensive task.
Note: {@code RateLimiter} does not provide fairness guarantees. @author Dimitris Andreou @since 13.0
com.linkedin.r2.transport.http.client.RateLimiter
@author Steven Ihde @version $Revision: $
org.voltdb.client.exampleutils.RateLimiter
A simple rate limiter that can be used to bind an asynchronous application/benchmark to a maximum transactional rate, preventing firehosing or providing a fixed expected throughput for performance validation (latency review at specific rates). @author Seb Coursol @since 2.0

Examples of com.google.common.util.concurrent.RateLimiter

     * allow for a more memory efficient solution if we know the sstable don't overlap (see
     * LeveledCompactionStrategy for instance).
     */
    public List<ICompactionScanner> getScanners(Collection<SSTableReader> sstables, Range<Token> range)
    {
        RateLimiter limiter = CompactionManager.instance.getRateLimiter();
        ArrayList<ICompactionScanner> scanners = new ArrayList<ICompactionScanner>();
        for (SSTableReader sstable : sstables)
            scanners.add(sstable.getScanner(range, limiter));
        return scanners;
    }

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter


        // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
        // max rate is scaled by the number of nodes in the cluster (CASSANDRA-5272).
        int throttleInKB = DatabaseDescriptor.getHintedHandoffThrottleInKB()
                           / (StorageService.instance.getTokenMetadata().getAllEndpoints().size() - 1);
        RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);


        boolean finished = false;
        delivery:
        while (true)
        {
            long now = System.currentTimeMillis();
            QueryFilter filter = QueryFilter.getSliceFilter(epkey,
                                                            SystemKeyspace.HINTS_CF,
                                                            startColumn,
                                                            ByteBufferUtil.EMPTY_BYTE_BUFFER,
                                                            false,
                                                            pageSize,
                                                            now);


            ColumnFamily hintsPage = ColumnFamilyStore.removeDeleted(hintStore.getColumnFamily(filter), (int) (now / 1000));


            if (pagingFinished(hintsPage, startColumn))
            {
                logger.info("Finished hinted handoff of {} rows to endpoint {}", rowsReplayed, endpoint);
                finished = true;
                break;
            }


            // check if node is still alive and we should continue delivery process
            if (!FailureDetector.instance.isAlive(endpoint))
            {
                logger.info("Endpoint {} died during hint delivery; aborting ({} delivered)", endpoint, rowsReplayed);
                break;
            }


            List<WriteResponseHandler> responseHandlers = Lists.newArrayList();
            for (final Column hint : hintsPage)
            {
                // check if hints delivery has been paused during the process
                if (hintedHandOffPaused)
                {
                    logger.debug("Hints delivery process is paused, aborting");
                    break delivery;
                }


                // Skip tombstones:
                // if we iterate quickly enough, it's possible that we could request a new page in the same millisecond
                // in which the local deletion timestamp was generated on the last column in the old page, in which
                // case the hint will have no columns (since it's deleted) but will still be included in the resultset
                // since (even with gcgs=0) it's still a "relevant" tombstone.
                if (!hint.isLive(System.currentTimeMillis()))
                    continue;


                startColumn = hint.name();


                ByteBuffer[] components = comparator.split(hint.name());
                int version = Int32Type.instance.compose(components[1]);
                DataInputStream in = new DataInputStream(ByteBufferUtil.inputStream(hint.value()));
                RowMutation rm;
                try
                {
                    rm = RowMutation.serializer.deserialize(in, version);
                }
                catch (UnknownColumnFamilyException e)
                {
                    logger.debug("Skipping delivery of hint for deleted columnfamily", e);
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }
                catch (IOException e)
                {
                    throw new AssertionError(e);
                }


                for (UUID cfId : rm.getColumnFamilyIds())
                {
                    if (hint.maxTimestamp() <= SystemKeyspace.getTruncatedAt(cfId))
                    {
                        logger.debug("Skipping delivery of hint for truncated columnfamily {}", cfId);
                        rm = rm.without(cfId);
                    }
                }


                if (rm.isEmpty())
                {
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }


                MessageOut<RowMutation> message = rm.createMessage();
                rateLimiter.acquire(message.serializedSize(MessagingService.current_version));
                Runnable callback = new Runnable()
                {
                    public void run()
                    {
                        rowsReplayed.incrementAndGet();

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter


        // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
        // max rate is scaled by the number of nodes in the cluster (CASSANDRA-5272).
        int throttleInKB = DatabaseDescriptor.getHintedHandoffThrottleInKB()
                           / (StorageService.instance.getTokenMetadata().getAllEndpoints().size() - 1);
        RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);


        delivery:
        while (true)
        {
            QueryFilter filter = QueryFilter.getSliceFilter(epkey,
                                                            new QueryPath(SystemTable.HINTS_CF),
                                                            startColumn,
                                                            ByteBufferUtil.EMPTY_BYTE_BUFFER,
                                                            false,
                                                            pageSize);


            ColumnFamily hintsPage = ColumnFamilyStore.removeDeleted(hintStore.getColumnFamily(filter),
                                                                     (int) (System.currentTimeMillis() / 1000));


            if (pagingFinished(hintsPage, startColumn))
                break;


            // check if node is still alive and we should continue delivery process
            if (!FailureDetector.instance.isAlive(endpoint))
            {
                logger.info("Endpoint {} died during hint delivery; aborting ({} delivered)", endpoint, rowsReplayed);
                return;
            }


            List<WriteResponseHandler> responseHandlers = Lists.newArrayList();


            for (final IColumn hint : hintsPage.getSortedColumns())
            {
                // check if hints delivery has been paused during the process
                if (hintedHandOffPaused)
                {
                    logger.debug("Hints delivery process is paused, aborting");
                    break delivery;
                }


                // Skip tombstones:
                // if we iterate quickly enough, it's possible that we could request a new page in the same millisecond
                // in which the local deletion timestamp was generated on the last column in the old page, in which
                // case the hint will have no columns (since it's deleted) but will still be included in the resultset
                // since (even with gcgs=0) it's still a "relevant" tombstone.
                if (!hint.isLive())
                    continue;


                startColumn = hint.name();


                ByteBuffer[] components = comparator.split(hint.name());
                int version = Int32Type.instance.compose(components[1]);
                DataInputStream in = new DataInputStream(ByteBufferUtil.inputStream(hint.value()));
                RowMutation rm;
                try
                {
                    rm = RowMutation.serializer.deserialize(in, version);
                }
                catch (UnknownColumnFamilyException e)
                {
                    logger.debug("Skipping delivery of hint for deleted columnfamily", e);
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }
                catch (IOException e)
                {
                    throw new AssertionError(e);
                }


                Map<UUID, Long> truncationTimesCache = new HashMap<UUID, Long>();
                for (UUID cfId : ImmutableSet.copyOf((rm.getColumnFamilyIds())))
                {
                    Long truncatedAt = truncationTimesCache.get(cfId);
                    if (truncatedAt == null)
                    {
                        ColumnFamilyStore cfs = Table.open(rm.getTable()).getColumnFamilyStore(cfId);
                        truncatedAt = cfs.getTruncationTime();
                        truncationTimesCache.put(cfId, truncatedAt);
                    }


                    if (hint.maxTimestamp() < truncatedAt)
                    {
                        logger.debug("Skipping delivery of hint for truncated columnfamily {}" + cfId);
                        rm = rm.without(cfId);
                    }
                }


                if (rm.isEmpty())
                {
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }


                MessageOut<RowMutation> message = rm.createMessage();
                rateLimiter.acquire(message.serializedSize(MessagingService.current_version));
                Runnable callback = new Runnable()
                {
                    public void run()
                    {
                        rowsReplayed.incrementAndGet();

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter


        output.println("total,interval_op_rate,interval_key_rate,latency,95th,99.9th,elapsed_time");


        int itemsPerThread = client.getKeysPerThread();
        int modulo = client.getNumKeys() % threadCount;
        RateLimiter rateLimiter = RateLimiter.create(client.getMaxOpsPerSecond());


        // creating required type of the threads for the test
        for (int i = 0; i < threadCount; i++) {
            if (i == threadCount - 1)
                itemsPerThread += modulo; // last one is going to handle N + modulo items

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter


        // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
        // max rate is scaled by the number of nodes in the cluster (CASSANDRA-5272).
        int throttleInKB = DatabaseDescriptor.getHintedHandoffThrottleInKB()
                           / (StorageService.instance.getTokenMetadata().getAllEndpoints().size() - 1);
        RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);


        delivery:
        while (true)
        {
            long now = System.currentTimeMillis();
            QueryFilter filter = QueryFilter.getSliceFilter(epkey,
                                                            SystemKeyspace.HINTS_CF,
                                                            startColumn,
                                                            ByteBufferUtil.EMPTY_BYTE_BUFFER,
                                                            false,
                                                            pageSize,
                                                            now);


            ColumnFamily hintsPage = ColumnFamilyStore.removeDeleted(hintStore.getColumnFamily(filter), (int) (now / 1000));


            if (pagingFinished(hintsPage, startColumn))
                break;


            // check if node is still alive and we should continue delivery process
            if (!FailureDetector.instance.isAlive(endpoint))
            {
                logger.info("Endpoint {} died during hint delivery; aborting ({} delivered)", endpoint, rowsReplayed);
                return;
            }


            List<WriteResponseHandler> responseHandlers = Lists.newArrayList();
            Map<UUID, Long> truncationTimesCache = new HashMap<UUID, Long>();
            for (final Column hint : hintsPage)
            {
                // check if hints delivery has been paused during the process
                if (hintedHandOffPaused)
                {
                    logger.debug("Hints delivery process is paused, aborting");
                    break delivery;
                }


                // Skip tombstones:
                // if we iterate quickly enough, it's possible that we could request a new page in the same millisecond
                // in which the local deletion timestamp was generated on the last column in the old page, in which
                // case the hint will have no columns (since it's deleted) but will still be included in the resultset
                // since (even with gcgs=0) it's still a "relevant" tombstone.
                if (!hint.isLive(System.currentTimeMillis()))
                    continue;


                startColumn = hint.name();


                ByteBuffer[] components = comparator.split(hint.name());
                int version = Int32Type.instance.compose(components[1]);
                DataInputStream in = new DataInputStream(ByteBufferUtil.inputStream(hint.value()));
                RowMutation rm;
                try
                {
                    rm = RowMutation.serializer.deserialize(in, version);
                }
                catch (UnknownColumnFamilyException e)
                {
                    logger.debug("Skipping delivery of hint for deleted columnfamily", e);
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }
                catch (IOException e)
                {
                    throw new AssertionError(e);
                }


                truncationTimesCache.clear();
                for (UUID cfId : ImmutableSet.copyOf((rm.getColumnFamilyIds())))
                {
                    Long truncatedAt = truncationTimesCache.get(cfId);
                    if (truncatedAt == null)
                    {
                        ColumnFamilyStore cfs = Keyspace.open(rm.getKeyspaceName()).getColumnFamilyStore(cfId);
                        truncatedAt = cfs.getTruncationTime();
                        truncationTimesCache.put(cfId, truncatedAt);
                    }


                    if (hint.maxTimestamp() < truncatedAt)
                    {
                        logger.debug("Skipping delivery of hint for truncated columnfamily {}" + cfId);
                        rm = rm.without(cfId);
                    }
                }


                if (rm.isEmpty())
                {
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }


                MessageOut<RowMutation> message = rm.createMessage();
                rateLimiter.acquire(message.serializedSize(MessagingService.current_version));
                Runnable callback = new Runnable()
                {
                    public void run()
                    {
                        rowsReplayed.incrementAndGet();

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter

     * allow for a more memory efficient solution if we know the sstable don't overlap (see
     * LeveledCompactionStrategy for instance).
     */
    public List<ICompactionScanner> getScanners(Collection<SSTableReader> sstables, Range<Token> range)
    {
        RateLimiter limiter = CompactionManager.instance.getRateLimiter();
        ArrayList<ICompactionScanner> scanners = new ArrayList<ICompactionScanner>();
        for (SSTableReader sstable : sstables)
            scanners.add(sstable.getScanner(range, limiter));
        return scanners;
    }

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter

        logger.debug("Started replayAllFailedBatches");


        // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
        // max rate is scaled by the number of nodes in the cluster (same as for HHOM - see CASSANDRA-5272).
        int throttleInKB = DatabaseDescriptor.getBatchlogReplayThrottleInKB() / StorageService.instance.getTokenMetadata().getAllEndpoints().size();
        RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);


        try
        {
            UntypedResultSet page = executeInternal(String.format("SELECT id, data, written_at, version FROM %s.%s LIMIT %d",
                                                                  Keyspace.SYSTEM_KS,

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter


        // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
        // max rate is scaled by the number of nodes in the cluster (CASSANDRA-5272).
        int throttleInKB = DatabaseDescriptor.getHintedHandoffThrottleInKB()
                           / (StorageService.instance.getTokenMetadata().getAllEndpoints().size() - 1);
        RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);


        delivery:
        while (true)
        {
            long now = System.currentTimeMillis();
            QueryFilter filter = QueryFilter.getSliceFilter(epkey,
                                                            SystemKeyspace.HINTS_CF,
                                                            startColumn,
                                                            ByteBufferUtil.EMPTY_BYTE_BUFFER,
                                                            false,
                                                            pageSize,
                                                            now);


            ColumnFamily hintsPage = ColumnFamilyStore.removeDeleted(hintStore.getColumnFamily(filter), (int) (now / 1000));


            if (pagingFinished(hintsPage, startColumn))
                break;


            // check if node is still alive and we should continue delivery process
            if (!FailureDetector.instance.isAlive(endpoint))
            {
                logger.info("Endpoint {} died during hint delivery; aborting ({} delivered)", endpoint, rowsReplayed);
                return;
            }


            List<WriteResponseHandler> responseHandlers = Lists.newArrayList();
            Map<UUID, Long> truncationTimesCache = new HashMap<UUID, Long>();
            for (final Column hint : hintsPage)
            {
                // check if hints delivery has been paused during the process
                if (hintedHandOffPaused)
                {
                    logger.debug("Hints delivery process is paused, aborting");
                    break delivery;
                }


                // Skip tombstones:
                // if we iterate quickly enough, it's possible that we could request a new page in the same millisecond
                // in which the local deletion timestamp was generated on the last column in the old page, in which
                // case the hint will have no columns (since it's deleted) but will still be included in the resultset
                // since (even with gcgs=0) it's still a "relevant" tombstone.
                if (!hint.isLive(System.currentTimeMillis()))
                    continue;


                startColumn = hint.name();


                ByteBuffer[] components = comparator.split(hint.name());
                int version = Int32Type.instance.compose(components[1]);
                DataInputStream in = new DataInputStream(ByteBufferUtil.inputStream(hint.value()));
                RowMutation rm;
                try
                {
                    rm = RowMutation.serializer.deserialize(in, version);
                }
                catch (UnknownColumnFamilyException e)
                {
                    logger.debug("Skipping delivery of hint for deleted columnfamily", e);
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }
                catch (IOException e)
                {
                    throw new AssertionError(e);
                }


                truncationTimesCache.clear();
                for (UUID cfId : ImmutableSet.copyOf((rm.getColumnFamilyIds())))
                {
                    Long truncatedAt = truncationTimesCache.get(cfId);
                    if (truncatedAt == null)
                    {
                        ColumnFamilyStore cfs = Keyspace.open(rm.getKeyspaceName()).getColumnFamilyStore(cfId);
                        truncatedAt = cfs.getTruncationTime();
                        truncationTimesCache.put(cfId, truncatedAt);
                    }


                    if (hint.maxTimestamp() < truncatedAt)
                    {
                        logger.debug("Skipping delivery of hint for truncated columnfamily {}" + cfId);
                        rm = rm.without(cfId);
                    }
                }


                if (rm.isEmpty())
                {
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }


                MessageOut<RowMutation> message = rm.createMessage();
                rateLimiter.acquire(message.serializedSize(MessagingService.current_version));
                Runnable callback = new Runnable()
                {
                    public void run()
                    {
                        rowsReplayed.incrementAndGet();

View Full Code Here

Examples of com.google.common.util.concurrent.RateLimiter


        // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
        // max rate is scaled by the number of nodes in the cluster (CASSANDRA-5272).
        int throttleInKB = DatabaseDescriptor.getHintedHandoffThrottleInKB()
                           / (StorageService.instance.getTokenMetadata().getAllEndpoints().size() - 1);
        RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);


        delivery:
        while (true)
        {
            long now = System.currentTimeMillis();
            QueryFilter filter = QueryFilter.getSliceFilter(epkey,
                                                            SystemKeyspace.HINTS_CF,
                                                            startColumn,
                                                            ByteBufferUtil.EMPTY_BYTE_BUFFER,
                                                            false,
                                                            pageSize,
                                                            now);


            ColumnFamily hintsPage = ColumnFamilyStore.removeDeleted(hintStore.getColumnFamily(filter), (int) (now / 1000));


            if (pagingFinished(hintsPage, startColumn))
                break;


            // check if node is still alive and we should continue delivery process
            if (!FailureDetector.instance.isAlive(endpoint))
            {
                logger.info("Endpoint {} died during hint delivery; aborting ({} delivered)", endpoint, rowsReplayed);
                return;
            }


            List<WriteResponseHandler> responseHandlers = Lists.newArrayList();


            for (final Column hint : hintsPage)
            {
                // check if hints delivery has been paused during the process
                if (hintedHandOffPaused)
                {
                    logger.debug("Hints delivery process is paused, aborting");
                    break delivery;
                }


                // Skip tombstones:
                // if we iterate quickly enough, it's possible that we could request a new page in the same millisecond
                // in which the local deletion timestamp was generated on the last column in the old page, in which
                // case the hint will have no columns (since it's deleted) but will still be included in the resultset
                // since (even with gcgs=0) it's still a "relevant" tombstone.
                if (!hint.isLive(System.currentTimeMillis()))
                    continue;


                startColumn = hint.name();


                ByteBuffer[] components = comparator.split(hint.name());
                int version = Int32Type.instance.compose(components[1]);
                DataInputStream in = new DataInputStream(ByteBufferUtil.inputStream(hint.value()));
                RowMutation rm;
                try
                {
                    rm = RowMutation.serializer.deserialize(in, version);
                }
                catch (UnknownColumnFamilyException e)
                {
                    logger.debug("Skipping delivery of hint for deleted columnfamily", e);
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }
                catch (IOException e)
                {
                    throw new AssertionError(e);
                }


                Map<UUID, Long> truncationTimesCache = new HashMap<UUID, Long>();
                for (UUID cfId : ImmutableSet.copyOf((rm.getColumnFamilyIds())))
                {
                    Long truncatedAt = truncationTimesCache.get(cfId);
                    if (truncatedAt == null)
                    {
                        ColumnFamilyStore cfs = Keyspace.open(rm.getKeyspaceName()).getColumnFamilyStore(cfId);
                        truncatedAt = cfs.getTruncationTime();
                        truncationTimesCache.put(cfId, truncatedAt);
                    }


                    if (hint.maxTimestamp() < truncatedAt)
                    {
                        logger.debug("Skipping delivery of hint for truncated columnfamily {}" + cfId);
                        rm = rm.without(cfId);
                    }
                }


                if (rm.isEmpty())
                {
                    deleteHint(hostIdBytes, hint.name(), hint.maxTimestamp());
                    continue;
                }


                MessageOut<RowMutation> message = rm.createMessage();
                rateLimiter.acquire(message.serializedSize(MessagingService.current_version));
                Runnable callback = new Runnable()
                {
                    public void run()
                    {
                        rowsReplayed.incrementAndGet();

View Full Code Here

Examples of com.linkedin.r2.transport.http.client.RateLimiter

      }
    };




    ScheduledExecutorService s = Executors.newSingleThreadScheduledExecutor();
    RateLimiter limiter = new RateLimiter(period, period, period, s);
    limiter.setPeriod(period);
    long start = System.currentTimeMillis();
    long lowTolerance = (total * period) * 4 / 5;
    long highTolerance = (total * period) * 5 / 4;
    for (int i = 0; i < total * period; i++)
    {
      limiter.submit(incr);
    }
    Assert.assertTrue(latch.await(highTolerance, TimeUnit.MILLISECONDS),
                      "Should have finished within " + highTolerance + "ms");
    long t = System.currentTimeMillis() - start;
    Assert.assertTrue(t > lowTolerance, "Should have finished after " + lowTolerance + "ms (took " + t + ")");

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