Monitoring Big Data Systems Done "The Simple Way"

Demi Ben-Ari - CTO @ Panorays

About Me

Demi Ben-Ari, Co-Founder & CTO @ Panorays● BS’c Computer Science – Academic College Tel-Aviv Yaffo● Co-Founder “Big Things” Big Data Community

In the Past:● Sr. Data Engineer - Windward● Team Leader & Sr. Java Software Engineer,

Missile defense and Alert System - “Ofek” – IAFInterested in almost every kind of technology – A True Geek

Agenda

● A lot of (NOT) funny Jokes● Problem definition and Environment● Monitoring pipeline solutions

○ Metrics○ Datastore○ Dashboards○ Alerting

● Summary● (Not going to address Service discovery and monitoring)

Say “Distributed”, Say “Big Data”,Say….

What is Big Data (IMHO)? And What to Monitor?● Systems involving the “3 Vs”:

What are the right questions we want to ask?○ Volume - How much?

■ Amount per second / minute / hour / day….■ Gigabytes, Terabytes, Petabytes…

○ Velocity - How fast?■ Count per second / minute / hour / day….

○ Variety ■ What kind? (Difference) ■ Sensor Data, Logs, Data Streams, Financial Transactions, Geo Locations...

Monolith Structure

OS CPU Memory Disk

Processes Java Application Server

Database

Web Server

Load Balancer

Users - Other Applications

Monitoring System

UI

Distributed Microservices Architecture

Service A

Queue

DB

Service B

DBCache

Cache DBService C

Web Server

DB

Analytics Cluster

Master

Slave Slave Slave

Monitoring System???

Some basic concepts

Basic Concepts● Monitoring

○ Collecting, processing, aggregating, and displaying real-time quantitative data about a system

● White-box○ Monitoring based on metrics exposed by the internals of the system○ logs, interfaces JMX of JVM, etc

● Black-box ○ Testing externally visible behavior as a user would see it.

● Dashboard○ An application that provides a summary view of a service’s core metrics.

Basic Concepts● Alert

○ A notification intended to be read by a human and that is pushed to a system such as a bug or ticket queue, an email alias or a pager.

● Root cause○ A defect in a software or human system that - if repaired, instills confidence that this

event won’t happen again in the same way.● Node and machine

○ Used interchangeably to indicate a single instance (physical server, virtual machine or container). There might be multiple services worth monitoring on a single machine.

● Push○ Any change to a service’s running software or its configuration.

● KPI - Key Performance Indicator

Data flow and Environment(Our Use Case)

Data Flow Diagram

External Data

Source

Analytics Layers

Data Pipeline

Parsed Raw

Entity Resolution Process

Building insightson top of the entities

Data Output Layer

Anomaly Detection

Trends

UI for End Users

Environment Description

Cluster

Dev TestingLive

Staging ProductionEnv

OB1K

RESTful Java Services

Situations

MongoDB + Spark

Worker 1

Worker 2

….

….

…

…

Worker N

Spark Cluster

Master

Write

Read

MasterSahrded MongoDB

Replica Set

Cassandra + Spark

Worker 1

Worker 2

….

….

…

…

Worker N

Cassandra Cluster

Spark Cluster

Write

Read

Cassandra + Serving

Cassandra Cluster

Write

Read

UI ClientUI Client

UI ClientUI Client

Web ServiceWeb

ServiceWeb ServiceWeb

Service

Problems● Multiple physical servers

● Multiple logical services

● Want Scaling => More Servers

● Even if you had all of the metrics○ You’ll have an overflow of the data

● Your monitoring becomes a “Big Data” problem itself

The what really “Distributed” Means

The DevOps Guy

(It might be you)

So...Let’s Start!

Report to Where?● We chose: ● Graphite (InfluxDB) + Grafana● Can correlate System and

Application metrics in one place :)

Report to Where?● Save DevOps efforts if you’re willing to Pay :)● Hosted Graphite

○ https://www.hostedgraphite.com/

● Throwing the “Big Data” volume monitoring problem at someone else

Connections Connections...

http://www.mememaker.net/meme/connections-connections-everywhere2/

Drivers to Datastores● Actions they usually do:

○ Open connection○ Apply actions

■ Select■ Insert■ Update■ Delete

○ Close connection

● Do you monitor each?○ Hint: Yes!!!! Hell Yes!!!

● Creating a wrapper in any programming language and reporting the metrics○ Count, execution times, errors…○ A bit of Infrastructure code that will give great visibility

Monitoring Operation System

Monitoring Operation System Metrics● What to measure:

○ CPU○ Memory○ Disk Space

● How to measure:○ CollectD or StatsD reporting to Graphite○ New Relic

■ Nice and easy UI■ Even the free account gives great tool■ Alerting of thresholds

Monitoring Cassandra

Monitoring Cassandra● OpsCenter - by DataStax

Monitoring Cassandra● Is the enough?...

We can connect it to Graphite also (Blog: “Monitoring the hell out of

Cassandra”)

● Plug & Play the metrics to Graphite - Internal Cassandra mechanism

● Back to the basics: dstat, iostat, iotop, jstack

Monitoring Cassandra

Monitoring Cassandra - Alternative

Monitoring Cassandra - Some more :)● Cyanite: http://cyanite.io/

Graphite with Cassandra backend as a datasource.

● Nodetool - Cassandra tool

● Back to the basics: dstat, iostat, iotop, jstack

Some help from “the Cloud”

Monitoring via AWS’s CloudWatch

Google Stackdriver (GCP)● Can integrate both GCP and Amazon accounts

Monitoring Spark

What to monitor in an Apache Spark Cluster● Application execution

● Resource consumption and allocation

● Task Failures

● Environment and Amount of servers

● Physical OS metrics

● Infrastructure services

Ways to Monitoring Spark● Sending Metrics: Spark → Graphite (Execution)

● http://spark.apache.org/docs/latest/monitoring.html

Ways to Monitoring Spark● Sending Metrics: Spark → Graphite (JVM metrics)

● http://spark.apache.org/docs/latest/monitoring.html

Ways to Monitoring Spark● Grafana-spark-dashboards

○ Blog: http://www.hammerlab.org/2015/02/27/monitoring-spark-with-graphite-and-grafana/

● Spark UI - Online on each application running● Spark History Server - Offline (After application finishes)● Spark REST API

○ Querying via inner tools to do ad-hoc monitoring

● Back to the basics: dstat, iostat, iotop, jstack● Blog post by Tzach Zohar - “Tips from the Trenches”

Monitoring Your Data

https://memegenerator.net/instance/53617544

Data Questions?

● Did all of the computation occur?

● Are there any data layers missing?

● How much data do we have? (Volume)

● Is all of the data in the Database?

Data Answers!● KISS (Keep it simple stupid)

● Jenkins + Maven (JUnit) for the rescue

● Creating a maven “monitoring” project.○ Running scheduled tasks, each for the relevant data source

■ Database data existence

■ S3 files existence

■ Data flow that keeps on coming from sensors

■ (Any other data source that you can imagine…)

○ Scheduled task that write amount metrics to Graphite -> Dashboards

○ Report task execution to Graphite

Data Answers!● The method doesn’t really matter, as long as you:

○ Can follow the results over time

○ Know what your data flow and know where things might fail

○ It’s easy for anyone to add more monitoring

(For the ones that add the new data each time…)

○ It don’t trust others to add monitoring

(It will always end up the DevOps’s “fault” -> No monitoring will be

applied)

Logging?Monitoring?

https://lh4.googleusercontent.com/DFVcH-E5XKj8cbhEtI0qabmf_wwVqWWvk0pK5H5rnC_kVxY2tXClKfzV-LvAH61YRLJUEvtO9amjWfjcY4Z57VBYCuQ95_hdAVEHgLAuepJiArH0wJERWuzzmgnPysCiIA

● Elastic● Architecture:

Server

Server

Server

ELK - Elasticsearch + Logstash + Kibana

Shippers

Queue

Indexer Web UIStorage

● (Simpler) Architecture:○ The problem: Log42 only works with TCP :( => Log4J2 works with UDP too

Server

Server

Server

ELK - Elasticsearch + Logstash + Kibana

Indexer Web UIStorage

TCP / UDP

ELK - Elasticsearch + Logstash + Kibana

http://www.digitalgov.gov/2014/05/07/analyzing-search-data-in-real-time-to-drive-decisions/

ELK - Elasticsearch + Logstash + Kibana

http://blog.takipi.com/log-management-tools-face-off-splunk-vs-logstash-vs-sumo-logic/

Who else Logs?

● Graylog2

● ….

● Logging As a Service :)

○ Logz.io (http://logz.io/blog/deploy-elk-production)

○ Logly

○ sematext

How does it look in real life?

● http://www.digitalgov.gov/2015/01/07/elk/● http://www.ragedsyscoder.com/monitoring-slides/file/img/tvs.jpg

Did someone say “Dashboard”?

http://www.funpic.hu/_files/pictures/original/86/71/27186.jpg

Redash● http://redash.io/● Open Source: https://github.com/getredash/redash● Came out as one of many Open source tool by Everything.me● Created and Maintained by Arik Fraimovich (You rock!)● Written in Python● Has an on-premise and hosted solution

רןאאקמ●

Redash - Data Sources

Redash - Screenshots

Redash - Screenshots

Redash - the “Why?”● Having multiple data sources in the organization

● Wanting to see all a combination of data sources in one place

● It’s open source and ready to use

● Why implement fancy UI and spend a lot of time?!?!?

● So...just use it!

Alerting

Alerting● Syren - Open source● Reporting to:

○ Email, Flowdock, HipChat, HTTP,

Hubot, IRCcat, PagerDuty,

Pushover, SLF4J, Slack, SNMP, Twilio

ELK - And what about alerting???● Elastalert

● http://engineeringblog.yelp.com/2015/10/elastalert-alerting-at-scale-with-elasticsearch.html● http://engineeringblog.yelp.com/2016/03/elastalert-part-two.html

Some more alerting● Cloudwatch and Stackdriver has their own alerting mechanism● New Relic has it’s own alerting too● Even with our Jenkins tests we’ve created alerting via emails

○ Beware of “Spam”

● Find which solution you would like as long as:○ You can notice what is wrong => when it’s wrong ○ Be able to “Acknowledge” your errors○ Do something you won’t be able to ignore :)

Summary - Monitoring Stack

Alerting

Metrics Collection

Datastore

Dashboard

Data Monitoring

Log Monitoring

Conclusions● Correlating Application and System metrics!!!!● Ask the right monitoring questions and answer them with Dashboards● KISS - simple is key, what’s hard, we tend not to do at all● Alert about what you can actually react to (And to the relevant person)● Measure whatever you can - only way to know if you’re improving● Monitor your business KPIs too.

● If all of the above is not enough,

Graphs are fricking cool!

http://www.rantlifestyle.com/2013/09/23/how-happy-this-baby-is-will-shock-you/

Questions?

�Demi Ben-Ari● LinkedIn● Twitter: @demibenari● Blog: http://progexc.blogspot.com/● Email: demi.benari@gmail.com● “Big Things” Community�Meetup, YouTube, Facebook, Twitter● GDG Cloud

Thanks! my contact:

Resources● Monitoring distributed systems - A case study in how Google monitors its

complex systems