Transitioning From SQL Server to MySQL: Lessons Learned Along The Way

Dylan Butler

• Who am I?

• Our MySQL project

• My team

• Our goals

• Final Architecture

• Findings along the way

• SQL Server vs. MySQL

• The Future

Agenda

Dylan Butler

Senior Database Administrator

SAS Institute

dylan.butler@sas.com

Twitter: @dylanbutler

linkedin.com\butlerdylan

Requirements:

• Take over support for databases of a critical web based application

• Migrate existing databases from MySQL 5.1

• Provide HA across data centers

• Must keep in MySQL

• Go live by end of year (approx. 9 months)

Our MySQL Project

• 3 SQL Server DBA’s

• 4 Oracle DBA’s

• Two sides of the team are very different

• How do we support a third database platform?

• Why us?

The Team

SQL Server Oracle

??

MySQL

• Use this as an opportunity to bring two sides of team closer together

• Build on processes already in place where possible

• Consolidate monitoring wherever possible

• Automate as much as we can

• Educate all team members along the way

• Documentation!

Goals

• Five node Galera (Percona XtraDB Cluster)• Two in one data center

• Two in the other

• An arbitrator (garbd) in a third building

• F5 using clustercheck

• Also using Percona Server• For less critical apps that don’t need HA

Final Architecture

Bldg 1 Bldg 2 Bldg 3

F5 VIP

App Servers

Backups

Options:

• Percona XtraBackup

• mysqldump

• Other• mysqlhotcopy

• MySQL Enterprise Backup

• Other physical options

Backups

Percona XtraBackup

• Online binary backup

• Great for disaster recovery of entire instance

• Not best solution for data recovery at database or table level

• Still would like to explore further

Backups

mysqldump

• Best fit for our needs.. Portability, non-blocking, data recovery, DR

• We are using InnoDB for all tables

• Using --single-transaction to avoid blocking (with InnoDB)

• Other options in use:• --flush-logs• --master-data=2• --routines• --triggers• --quick• --hex-blob• --all-databases

Backups

Jobs and other considerations

• Nightly full dump

• Hourly binary log flush and copy

• All backups and logs copied to network storage device

• Written to tape each night

• Another job to clean up older files

Backups

Monitoring and Performance

• Goal: Utilize existing tools where possible

• Zenoss• Linux Monitor ZenPack (ssh)

• MySQL Database Monitor (Core) ZenPack (Python)

• Server/Database attributes re-modeled every 12 hours

• 5 minute collection interval for monitors

• Event triggering

• Notification is built in.. we call a custom notification app

Monitoring

Goal: Take full advantage of what is included in MySQL

• Performance Schema• Enabled by default as of 5.6.6

• Sys Schema• Included starting in 5.7.7 but backwards compatible to 5.6

• Workbench

• Zenoss

Performance Data

Findings Along The Way

• We didn’t get it all right the first time

• Examples:• Collation

• SQL mode

• Federated storage engine

• Configuration (MySQL and Linux)- Swappiness (VM’s) – 1 for Percona Server, 10 for XtraDB Cluster

- For Galera clusters, increase the size of gcache

- Slow query log – turned off log_queries_not_using_indexes

- Timeout settings – net_read_timeout and net_write_timeout

Rework Needed

• Backups

• Security

• Performance Tuning

• Monitoring improvements

• More automation and documentation

• Patching

Still Needs Work

• Good and bad• SQL Server is a robust platform and toolset, but licensing adds up quickly

• MySQL offers most of the same functionality and features

• Security• I miss Active Directory

• Slight differences, but very similar permissions

• Need to lock down MySQL after install

• Backups• Lots more options in MySQL.. can be good and bad

SQL Server vs MySQL

• Jobs• cron is fine, but I do miss SQL Agent

• Quirks• Single line comments using -- must have a space after the –

• Functions – enable bin-log-trust-function-creators

• Tools• MySQL Workbench is decent, but it’s no SSMS

SQL Server vs MySQL

• Lots of growth in MySQL

• Probably more platforms• At least the addition of a NoSQL offering

Our Future

Thanks for attending!