The document discusses running virtualized Galera instances for high availability and discusses how Galera and virtualization can work together. It covers how Galera works with synchronous replication, popular virtualization solutions like KVM and containers, deploying Galera in virtualized environments including initialization, operations, storage, and networking considerations, and concludes by taking questions.

1. Running virtualized Galera instances for fun and
profit
Linux Conf Au 2014 - Sysadmin Miniconf
Raghavendra Prabhu
raghavendra.prabhu@percona.com
Percona
January 6th, 2013
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2. Outline
1 Introduction
2 Galera and Virtualization
3 Coming Together
4 Conclusion
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3. Introduction
Overview
Synchronous replication
Galera and PXC
Virtualization
High Availability
Commonality
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4. Galera and Virtualization
Galera/PXC
What are they
How do they work
MySQL Compatibility
Synchronous replication
Others
Google F1/Spanner
MySQL NDB
Sharding?
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5. Galera and Virtualization
Virtualization
Popular solutions
Xen, KVM, OpenStack
Containers - LXC, Docker, ZeroVM
Application-isolated virt
Application
Constraints
Advantages
Data-centers
WSCs and clusters
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6. Galera and Virtualization
Warehouse-scale
Clusters
Hadoop, Manta et.al.
Different from normal data-centers
Why?
Homogenity of hardware and stacks
Demands and constraints
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7. Coming Together
Current scenario
Popular Solutions
GlusterFS: FUSE
Sheepdog: QEMU
Application level clustering
How is this different
Can work with them
Galera and others
Hadoop
{No,New,}SQL
Mapreduce/Compute
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8. Coming Together
Scenarios
Necessity
Hardware of today
Saturation
WSC
High Availability
Migration
WANs
Isolation
Hosting
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9. Coming Together
Deployment I
Initialisation
Bootstrapping
Cloning
QCOW zero-copy: I/O
Reduced memory footprint: KSM
Thin-provisioning: Ballooning
Upgrades!
Load-balancing galera
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10. Coming Together
Deployment II
Operation
Migration
Live Migration: Streaming
Guest Agent
FTWRL: Xtrabackup
Shared storage
COW or COR
LAN v/s WAN
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11. Coming Together
Deployment III
Storage
Single host
VirtFS: share the root!
Works well with QCOW
Network
Latency
Synchronous replication!
Affects pre-commit stage
virtio-net/vhost-net
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12. Coming Together
Deployment IV
Misc
Backups
Dirty bitmaps
Roles
Throttling
Reader - Writer
Upgrades, maintenance
Non-homogenous hardware
Async replication support
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13. Conclusion
Thoughts?
Questions
Usage and Experience
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14. Conclusion
Me
Raghavendra Prabhu
http://wnohang.net/about
Software Engineer at Percona and Product Lead of PXC
https://launchpad.net/percona-xtradb-cluster
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