Ops 101

Asya KamskyPrincipal Community Advocate

MongoDB

Operational Database Landscape

RDBMS

Agility

MongoDB

{

_id : ObjectId("4c4ba5e5e8aabf3"),

employee_name: "Dunham, Justin",

department : "Marketing",

title : "Product Manager, Web",

report_up: "Neray, Graham",

pay_band: “C",

benefits : [

{ type :  "Health",

plan : "PPO Plus" },

{ type :   "Dental",

plan : "Standard" }

]

}

Document Data Model

Relational MongoDB

{ first_name: ‘Paul’, surname: ‘Miller’, city: ‘London’, location: [45.123,47.232], cars: [ { model: ‘Bentley’, year: 1973, value: 100000, … }, { model: ‘Rolls Royce’, year: 1965, value: 330000, … } }}

Document Model Benefits

• Agility and flexibility– Data models can evolve easily– Companies can adapt to changes quickly

• Intuitive, natural data representation– Developers are more productive– Many types of applications are a good fit

• Reduces the need for joins, disk seeks– Programming is more simple– Performance can be delivered at scale

ShellCommand-line shell for interacting directly with database

Shell and Drivers

DriversDrivers for most popular programming languages and frameworks

> db.collection.insert({company:“10gen”, product:“MongoDB”})> > db.collection.findOne(){

“_id” : ObjectId(“5106c1c2fc629bfe52792e86”),

“company” : “10gen”“product” : “MongoDB”

}

Haskell

Scalability

Automatic Sharding

• Increase or decrease capacity as you go

• Automatic balancing

• Three types of sharding:

hash-based

range-based

tag-aware

Query Routing

• Multiple query optimization models

• Many sharding options appropriate for different apps

High Availability

• High Availability – Ensure application availability during many types of failures

• Disaster Recovery – Address the RTO and RPO goals for business continuity

• Maintenance – Perform upgrades and other maintenance operations with no application downtime

Availability Considerations

Replica Sets

• Replica Set – two or more copies

• “Self-healing” shard

• Addresses many concerns:

- High Availability

- Disaster Recovery

- Maintenance

Replica Set Benefits

Business Needs Replica Set Benefits

High Availability Automated failover

Disaster Recovery Hot backups offsite

Maintenance Rolling upgrades

Low Latency Locate data near users

Workload Isolation Read from designated nodes

Data Consistency Tunable Consistency

Performance

Better Data Locality

Performance

In-Memory Caching In-Place Updates

Performance at Scale

• Entertainment Company: 1,400 servers• Craigslist: 5B documents• Carfax: 11B documents• Tier 1 Bank: 30K ops/sec• Major Retailer: 50K ops/sec• Fed Agency: 500K ops/sec• Wordnik: 20B documents, 35,000 ops/sec

MongoDB Performance*

Top 5 Marketing Firm Government Agency Top 5 Investment Bank

Data Key/value 10+ fields, arrays, nested documents

20+ fields, arrays, nested documents

Queries Key-based1 – 100 docs/query80/20 read/write

Compound queriesRange queriesMapReduce20/80 read/write

Compound queriesRange queries50/50 read/write

Servers ~250 ~50 ~40

Ops/sec 1,200,000 500,000 30,000

* These figures are provided as examples. Your application governs your performance.

Key Deployment Considerations

Capacity Planning

• Requirements

• Testing

• Monitoring

Key Performance Considerations

Capacity Planning

• Requirements

• Testing

• Monitoring

Performance Tuning

• Understanding

• Adjusting

• Monitoring

Monitoring

Monitoring

• CLI and internal status commands• mongostat; mongotop; db.serverStatus()

• Plug-ins for munin, Nagios, cacti, etc.

• Integration via SNMP to other tools

• MMS

MongoDB Management ServiceCloud-based suite of services for managing MongoDB deployments

MongoDB Management Service

• Charts, custom dashboards and automated alerting

• Tracks 100+ metrics – performance, resource utilization, availability and response times

• 15,000+ users

Cloud-based suite of services for managing MongoDB deployments

• Backup and restore with

– point-in-time recovery,

– support for sharded clusters

Cloud-based suite of services for managing MongoDB deployments

• MMS On-Prem included with MongoDB Enterprise (backup coming soon)

MongoDB Management Service

A Picture Speaks a Thousand Words

Symptoms

High Use CPU Similar Query Pattern

Monitoring Best Practices

• Monitor Logs– Alert, escalate– Correlate

• Disk– Monitor

• Instrument/Monitor App (including logs!)• Know your application and application (write) characteristics