architectual comparison of apache apex and spark streaming
TRANSCRIPT
Architectural Comparison of Apache Apex and Spark Streaming
WebinarJune 8th 2016
Thomas Weise, Apache Apex PMC@thweise [email protected]
Next Gen Stream Data Processing• Data from variety of sources (IoT, Kafka, files, social media etc.)• Unbounded, continuous data streams
ᵒ Batch can be processed as stream (but a stream is not a batch)• (In-memory) Processing with temporal boundaries (windows)• Stateful operations: Aggregation, Rules, … -> Analytics• Results stored to variety of sinks or destinations
ᵒ Streaming application can also serve data with very low latency
2
Browser
Web Server
Kafka Input(logs)
Decompress, Parse, Filter
Dimensions Aggregate Kafka
LogsKafka
Batch vs. Streaming
Credit: Gyula Fóra & Márton Balassi: Large-Scale Stream Processing in the Hadoop Ecosystem
3
Architecture and FeaturesSpark Streaming Apex
Model micro-batch native streaming/data-in-motion
Language Java, Scala, client bindings Java (Scala)
API declarative compositional (DAG), declarative*
Locality data locality advanced processing locality
Latency high very low (millis)
Throughput very high very high
Scalability scheduler limit horizontal
Partitioning standard advanced (parallel pipes, unifiers)
Connector Library Limited (certification), externally maintained
Rich library of connectors and processors, part of Apex (Malhar)
4
OperabilitySpark Streaming Apex
State Management RDD, user code checkpointing
Recovery RDD lineage incremental (buffer server)
Processing Sem. exactly-once* end-to-end exactly-once
Backpressure user configuration Automatic (buffer server memory + disk)
Elasticity yes w/ limited control yes w/ full user control
Dynamic topology no yes
Security Kerberos Kerberos, RBAC*, LDAP*
Multi-tennancy depends on cluster manager YARN, full isolation
DevOps tools basic REST API, DataTorrent RTS
5
Apache Apex Features• In-memory stream processing platform
ᵒ Developed since 2012, ASF TLP since 04/2016• Unobtrusive Java API to express (custom) logic• Scale out, distributed, parallel• High throughput & low latency processing• Windowing (temporal boundary)• Reliability, fault tolerance, operability• Hadoop native• Compute locality, affinity• Dynamic updates, elasticity
6
7
Apex Platform Overview
8
Apache Apex Malhar Library
9
Application Development Model
A Stream is a sequence of data tuplesA typical Operator takes one or more input streams, performs computations & emits one or more output streams
• Each Operator is YOUR custom business logic in java, or built-in operator from our open source library• Operator has many instances that run in parallel and each instance is single-threaded
Directed Acyclic Graph (DAG) is made up of operators and streams
Directed Acyclic Graph (DAG)
Filtered
Stream
Output StreamTuple Tuple
Filtered Stream
Enriched Stream
Enriched
Stream
er
Operator
er
Operator
er
Operator
er
Operator
er
Operator
er
Operator
10
Streaming Windows
Application window Sliding window and tumbling window
Checkpoint window No artificial latency
11
Event time & Dimensions Computation
(All) : 5t=4:00 : 2t=5:00 : 3
k=A, t=4:00 : 2k=A, t=5:00 : 1k=B, t=5:00 : 2
(All) : 4t=4:00 : 2t=5:00 : 2
k=A, t=4:00 : 2
K=B, t=5:00 : 2
k=At=5:00
(All) : 1t=4:00 : 1
k=A, t=4:00 : 1
k=Bt=5:59
k=Bt=5:00
k=AT=4:30
k=At=4:00
Scalability• Large amount of data to process, arrival at high velocity
ᵒ Pipelining and partitioningᵒ Backpressure
• Partitioningᵒ Run same logic in multiple processes or threadsᵒ Each partition processes a subset of the data
• Apex supports partitioning out of the boxᵒ Different partitioning schemesᵒ Unificationᵒ Static & Dynamic Partitioningᵒ Separation of processing logic from scaling decisions
12
13
PartitioningNxM PartitionsUnifier
0 1 2 3
Logical DAG
0 1 2
1
1 Unifier
1
20
Logical Diagram
Physical Diagram with operator 1 with 3 partitions
0
Unifier
1a
1b
1c
2a
2b
Unifier 3
Physical DAG with (1a, 1b, 1c) and (2a, 2b): No bottleneck
Unifier
Unifier0
1a
1b
1c
2a
2b
Unifier 3
Physical DAG with (1a, 1b, 1c) and (2a, 2b): Bottleneck on intermediate Unifier
14
Advanced Partitioning
0
1a
1b
2 3 4Unifier
Physical DAG
0 4
3a2a1a
1b 2b 3b
Unifier
Physical DAG with Parallel Partition
Parallel Partition
Container
uopr
uopr1
uopr2
uopr3
uopr4
uopr1
uopr2
uopr3
uopr4
dopr
dopr
doprunifier
unifier
unifier
unifier
Container
Container
NIC
NIC
NIC
NIC
NIC
Container
NIC
Logical Plan
Execution Plan, for N = 4; M = 1
Execution Plan, for N = 4; M = 1, K = 2 with cascading unifiers
Cascading Unifiers
0 1 2 3 4
Logical DAG
15
Dynamic Partitioning
• Partitioning change while application is runningᵒ Change number of partitions at runtime based on statsᵒ Determine initial number of partitions dynamically
• Kafka operators scale according to number of kafka partitionsᵒ Supports re-distribution of state when number of partitions changeᵒ API for custom scaler or partitioner
2b
2c
3
2a
2d
1b
1a1a 2a
1b 2b
3
1a 2b
1b 2c 3b
2a
2d
3a
Unifiers not shown
16
How dynamic partitioning works• Partitioning decision (yes/no) by trigger (StatsListener)
ᵒ Pluggable component, can use any system or custom metricᵒ Externally driven partitioning example: KafkaInputOperator
• Stateful! ᵒ Uses checkpointed stateᵒ Ability to transfer state from old to new partitions (partitioner, customizable)ᵒ Steps:
• Call partitioner• Modify physical plan, rewrite checkpoints as needed• Undeploy old partitions from execution layer• Release/request container resources• Deploy new partitions (from rewritten checkpoint)
ᵒ No loss of data (buffered)ᵒ Incremental operation, partitions that don’t change continue processing
• API: Partitioner interface
17
Fault Tolerance• Operator state is checkpointed to persistent store
ᵒ Automatically performed by engine, no additional coding neededᵒ Asynchronous and distributed ᵒ In case of failure operators are restarted from checkpoint state
• Automatic detection and recovery of failed containersᵒ Heartbeat mechanismᵒ YARN process status notification
• Buffering to enable replay of data from recovered pointᵒ Fast, incremental recovery, spike handling
• Application master state checkpointedᵒ Snapshot of physical (and logical) planᵒ Execution layer change log
• In-memory PubSub• Stores results emitted by operator until committed• Handles backpressure / spillover to local disk• Ordering, idempotency
Operator 1
Container 1
BufferServer
Node 1
Operator 2
Container 2
Node 2
Buffer Server
18
Recovery Scenario… EW2, 1, 3, BW2, EW1, 4, 2, 1, BW1
sum0
… EW2, 1, 3, BW2, EW1, 4, 2, 1, BW1sum
7
… EW2, 1, 3, BW2, EW1, 4, 2, 1, BW1sum10
… EW2, 1, 3, BW2, EW1, 4, 2, 1, BW1sum
7
19
20
Processing GuaranteesAt-least-once• On recovery data will be replayed from a previous checkpoint
ᵒ No messages lostᵒ Default, suitable for most applications
• Can be used to ensure data is written once to storeᵒ Transactions with meta information, Rewinding output, Feedback
from external entity, Idempotent operationsAt-most-once• On recovery the latest data is made available to operator
ᵒ Useful in use cases where some data loss is acceptable and latest data is sufficient
Exactly-onceᵒ At-least-once + idempotency + transactional mechanisms (operator
logic) to achieve end-to-end exactly once behavior
End-to-End Exactly Once
21
• Becomes important when writing to external systems• Data should not be duplicated or lost in the external system even in
case of application failures• Common external systems
ᵒ Databasesᵒ Filesᵒ Message queues
• Platform support for at least once is a must so that no data is lost• Data duplication must still be avoided when data is replayed from
checkpointᵒ Operators implement the logic dependent on the external systemᵒ Platform provides checkpointing and repeatable windowing
22
Data Processing Pipeline ExampleApp Builder
23
Monitoring ConsoleLogical View
24
Monitoring ConsolePhysical View
25
Real-Time DashboardsReal Time Visualization
26
Maximize Revenue w/ real-time insightsPubMatic is the leading marketing automation software company for publishers. Through real-time analytics, yield management, and workflow automation, PubMatic enables publishers to make smarter inventory decisions and improve revenue performance
Business Need Apex based Solution Client Outcome
• Ingest and analyze high volume clicks & views in real-time to help customers improve revenue
- 200K events/second data flow
• Report critical metrics for campaign monetization from auction and client logs
- 22 TB/day data generated• Handle ever increasing traffic with
efficient resource utilization• Always-on ad network
• DataTorrent Enterprise platform, powered by Apache Apex
• In-memory stream processing• Comprehensive library of pre-built
operators including connectors• Built-in fault tolerance• Dynamically scalable• Management UI & Data Visualization
console
• Helps PubMatic deliver ad performance insights to publishers and advertisers in real-time instead of 5+ hours
• Helps Publishers visualize campaign performance and adjust ad inventory in real-time to maximize their revenue
• Enables PubMatic reduce OPEX with efficient compute resource utilization
• Built-in fault tolerance ensures customers can always access ad network
27
Industrial IoT applicationsGE is dedicated to providing advanced IoT analytics solutions to thousands of customers who are using their devices and sensors across different verticals. GE has built a sophisticated analytics platform, Predix, to help its customers develop and execute Industrial IoT applications and gain real-time insights as well as actions.
Business Need Apex based Solution Client Outcome
• Ingest and analyze high-volume, high speed data from thousands of devices, sensors per customer in real-time without data loss
• Predictive analytics to reduce costly maintenance and improve customer service
• Unified monitoring of all connected sensors and devices to minimize disruptions
• Fast application development cycle• High scalability to meet changing business
and application workloads
• Ingestion application using DataTorrent Enterprise platform
• Powered by Apache Apex• In-memory stream processing• Built-in fault tolerance• Dynamic scalability• Comprehensive library of pre-built
operators• Management UI console
• Helps GE improve performance and lower cost by enabling real-time Big Data analytics
• Helps GE detect possible failures and minimize unplanned downtimes with centralized management & monitoring of devices
• Enables faster innovation with short application development cycle
• No data loss and 24x7 availability of applications
• Helps GE adjust to scalability needs with auto-scaling
28
Smart energy applications
Silver Spring Networks helps global utilities and cities connect, optimize, and manage smart energy and smart city infrastructure. Silver Spring Networks receives data from over 22 million connected devices, conducts 2 million remote operations per year
Business Need Apex based Solution Client Outcome
• Ingest high-volume, high speed data from millions of devices & sensors in real-time without data loss
• Make data accessible to applications without delay to improve customer service
• Capture & analyze historical data to understand & improve grid operations
• Reduce the cost, time, and pain of integrating with 3rd party apps
• Centralized management of software & operations
• DataTorrent Enterprise platform, powered by Apache Apex
• In-memory stream processing• Pre-built operator • Built-in fault tolerance• Dynamically scalable• Management UI console
• Helps Silver Spring Networks ingest & analyze data in real-time for effective load management & customer service
• Helps Silver Spring Networks detect possible failures and reduce outages with centralized management & monitoring of devices
• Enables fast application development for faster time to market
• Helps Silver Spring Networks scale with easy to partition operators
• Automatic recovery from failures
Demo / Q&A
29
Resources
30
• Apache Apex - http://apex.apache.org/• Subscribe - http://apex.apache.org/community.html• Download - https://www.datatorrent.com/download/• Twitter
ᵒ @ApacheApex; Follow - https://twitter.com/apacheapexᵒ @DataTorrent; Follow – https://twitter.com/datatorrent
• Meetups - http://www.meetup.com/topics/apache-apex• Webinars - https://www.datatorrent.com/webinars/• Videos - https://www.youtube.com/user/DataTorrent• Slides - http://www.slideshare.net/DataTorrent/presentations • Startup Accelerator Program - Full featured enterprise product
ᵒ https://www.datatorrent.com/product/startup-accelerator/
31
We Are Hiring• [email protected]• Developers/Architects• QA Automation Developers• Information Developers• Build and Release• Community Leaders