For All Your Base, 2014, in Oxford. 30 minute overview of AWS, RDS and MySQL.

1. Scaling MySQL in AWS
All Your Base Conf, Oxford, UK
Laine Campbell, Co-Founder
October 17th, 2014

2. Who am I?
DB Architect, Entrepreneur and super hero…
Good hair, not overly clever, female pronouns

3. Who am I?
Humor - Self effacing, self aggrandizing, dry…
Cajun, rogueish, and I destroy everything I touch...

4. Who am I?
When in doubt, laugh

5. Who am I?
Happy Belated Ada Lovelace Day

6. Agenda
● Amazon options for implementation
● MySQL scaling patterns
● Resiliency
● Round it out
● War Stories

7. RDS and EC2/MySQL
A love story...

8. Amazon RDS (DBaaS)
Basic Operations Managed
Ease of Deployment
Supports Scaling via Replication
Resilient via Replication, EBS RAID, Multi-AZ, Multi-Region

9. What is Multi-AZ?
Automatic Failover, spread across availability zones
Significantly reduces impact of operations such as:
● Backups
● Replica Builds
● Patching

10. Managed Operations
● Backups and Recovery
● Provisioning
● Patching
● Auto Failover
● Replication

11. What does it cost?
● Instance tax: 35% - 37%
● Provisioned IOPS: 15%
● Lack of transparency - can increase downtime

12. What does it cost?
● Multi AZ Master - db.r3.8xlarge, 1 yr reserved
○ $17,312
● 3 replicas - b.r3.8xlarge, 1 yr reserved
○ $25,968
● Provisioned IOPS - general purpose (new)
○ 1 TB dataset = $6,144 (5 copies)
● Total Cost RDS = $49,424
● Off of RDS = $34,726

13. Cost Thoughts
● RDS costs $14,698/yr
○ DBA costs $144K/yr, = $108 hour (time off, productivity,
retention/churn)
○ Equals 136 hours of DBA time (3.5 weeks)
● Automating via EC2 is a one time job, RDS tax is ALWAYS
○ 5 clusters costs you 680 hours of DBA time (17 weeks)
○ 5 clusters, 3 years = 2,040 hours, or 51 weeks
○ What can your DBA do with an extra 51 weeks?

14. Other Costs
● Lock-in:
○ In 5.6, you can replicate out, making this moot.
○ You have to automate once out, you could have spent
this in the beginning.
● Lack of Visibility:
○ Dtrace, TCPDump, Top, VMStat, etc…
● Lack of Control:
○ Data Security, Shared Environments, Backups????
○ Restarts due to exploits, etc...

15. Amazon EC2, Roll Your Own
Build your own automation:
● Provisioning, with replication
● Configuration management
● Backup and recovery
● Instance registration
Other DBaaS Options such as Tesora Trove
● Community, free
● Enterprise starts at $25,000 for 50 instances
● don’t forget RDS, 5 clusters, 1 years = $73,440

16. Choosing RDS vs EC2

17. Why use RDS?
● Legacy apps that cannot use 5.6, and can accept <
99.65% SLAs
● Low volume/traffic applications for companies who
choose to not have their own operations expertise

18. Why use EC2?
● Want MariaDB or XtraDB Variants
● Want more flexibility in multi-region setups (before
5.6)
● Want portability to other clouds
● High performance and scale needs that require
access to the OS, and to the FULL DB instance

19. Storage Options in AWS
Type RDS EC2 Persistent Max
IOPS
Max
Throughput
Cost
Pure SSD No Yes No 100,000 390 MBps Free w/Instance Cost
EBS General
Purpose SSD
Yes Yes Yes 3,000 128 MBps $.10/GB/month
EBS PIOPS SSD Yes Yes Yes 4,000 128 MBps $.125/GB/month + $.
065/PIOPS/month
EBS Magnetic Yes Yes Yes 40-200 40-90 MBps $.05/GB/month + $.
05/million IOPS

20. Scaling MySQL at AWS

21. My Definition of Scaling
● Capacity is elastic and automated
● Performance stays reasonably consistent
● Availability scales
● Resiliency scales
● Operational visibility scales
● Backup and recovery scales

22. MySQL Workload Scaling
● Break out workloads to their own clusters
○ To facilitate sharding large data-sets horizontally
○ To segregate specific workload characteristics
● Evaluate each workload’s read/write needs
Total dataset size and growth
Data change delta (updates/deletes)

23. MySQL Workload Scaling
User Login/Profile
1 TB (1MM User)
20,000 iops peak
10% write
90% read
User Content
5 TB
500,000 iops peak
1% write
99% read
Site Metadata
5 GB
500 iops peak
25% write
Shard Candidate 75% read
Shard Candidate

24. MySQL Workload Scaling
Determine sharding size based on constraints
○ AWS Write IO
○ Replication Limits
○ Tolerance for large numbers of systems
○ Budget

25. MySQL Workload Scaling
Sharding Topology:
● Schema:Shard relationship 1:1
● Instance:Schema relationship 1:N
● Host:Instance relationship 1:1
Host 1
Instance 1
Shard 1 Shard 2

26. MySQL Workload Scaling
User Profile Data - 10 shards, hashable
○ Per Shard: 2,000 (500MB) iops, 200 wps (50MB), 100 GB storage
■ Two replication threads/shards per cluster
○ SSD General Purpose EBS, 2 300 GB Volumes Striped (
■ 1,800 IOPS, 6000 burst, 800 MBps
○ 3,600 rps (900 MBps) requires 2 replicas (500 MBps), +1 for
redundancy
○ 1 master, 1 failover, 3 replicas = 25 hosts, r3.2x lg
■ Memory = 61 GB > active dataset
■ Assumes read/write splitting
○ Total Cost = $48,600 instances + $18,000 storage = $66,600

28. MySQL Workload Scaling
Host 1
Instance 1
Shard 1
Instance 2
Keep Schema:Shard relationship 1:1
Change Schema:Instance relationship from 1:N to 1:1
Change Instance:Host relationship from 1:1 to 1:N
Shard 2

30. MySQL Workload Scaling
Summary
○ Final Constraint is Write IOPS
○ Sharding eliminates Constraint
○ There are ways to reduce those reads:
■ Caching
○ There are ways to reduce those writes:
■ Throttling concurrency with queuing and loose coupling to
keep write IO down
■ Compression! Native or application based
○ Moving storage to ephemeral SSD saves $$$$
■ If you truly can leverage backup and recovery with small
datasets

31. MySQL Workload Scaling
Master
Replica Replica
Failover
Shard 1
Master
Replica Replica
Failover
Shard 2

32. Resiliency Layers
● Sharding
○ Shard N = y% of traffic, where y = 1/Shards*100
○ Aka with 64 shards, one shard lost = 1.56%
● EBS Snapshots
○ Rapid redeployment of failed nodes (kill, rebuild)

33. Type of Change EC2 RDS Master
(Non Multi-AZ)
RDS Master
(Multi-AZ)
RDS Replica
Instance resize
up/down
Rolling Migrations Moderate
Downtime
Minimal
Downtime
Moderate Downtime
(take out of service)
EBS <-> PIOPS Severe Perf impact Severe Perf impact Minor Perf impact Severe Perf Impact
(take out of service)
PIOPS Amount
Change
Minor Perf impact Minor Perf impact Minor Perf impact Severe Perf Impact
(take out of service)
Disk Space Change
(add)
Severe Perf impact Severe Perf impact Minor Perf impact Severe Perf Impact
(take out of service)
Disk Space Change
(reduce)
Rolling Migrations Severe Downtime
(promote from
replica)
Minimal
Downtime
Moderate Downtime
(take out of service)

34. Power Up - Resiliency via Geography

35. MySQL Workload Scaling
S1 Master
US East 1
Replica Replica
S2 Failover
During failover, spawn replicas
US West 1
AZ 2 AZ 3
AZ 1
Future
Replica
Future
Replica
AZ 2 AZ 3
Nginx Nginx

36. Cluster Management and Failover
● Roll your own….
○ Config Mgmt
○ Automation Scripting
○ HAProxy
● Spend some dough
○ RDS
○ Continuent Tungsten
○ Scalearc
● Bleeding edge but clotting
○ Galera, via MariaDB or XtraDB Cluster
● Bleeding edge and fresh
○ Openstack, Trove and Tesora

37. Rounding it Out: Operational Visibility
● Monitoring and Alerting: Sensu (not Nagios)
● Time Series Trending: Graphite or OpenTSDB
● Graphing of Data: Grafana
● Log Aggregation and Management: Logstash or Splunk
● Application Monitoring: New Relic or AppDynamics

38. Rounding it Out: Backup and Recovery
● Sharding keeps systems small and agile
○ Snapshots for tactical kill and build
○ S3 for longer-term
○ Glacier forever
○ Offsite for Legal

39. Questions and Follow up
○ lcampbell@pythian.com
○ www.pythian.com
○ www.linkedin.com/lainecampbell
○ www.adafoundation.org