Is virtualization a good choice for SQL Server?

Denny Cherryhttp://www.mrdenny.commrdenny@mrdenny.com

twitter.com/mrdenny

2

About MeIndependent ConsultantFounder of SQL ExcursionsAuthor or Coauthor of 5 books8+ SQL Mag articlesDozens of other articlesMicrosoft MVPMicrosoft Certified Master

AgendaMajor Platform ChoicesBenefitsPitfallsDeciding FactorsLimits of VirtualizationManagement ToolsLicensing

Major Platform ChoicesVMware

ESX 1-3.5vSphere 4.0 – 4.1

VMware announced 4.1 will be the last version with a host console 7/30/2010

vSphere Hypervisor (ESXi) 4.0+Hyper-V

V1 and v2 (v3 will be in Windows 8)

BenefitsHardware CostsInstant Server DeploymentFree Server Redundancy

Live Migration – Hyper-VvMotion - VMware

Easy System Upgrades

Balloon Memory DriversUsed by host OS to request memory back

from the guest OSPrevents host of from paging physical

memory to the hosts swap fileShould be enabledLock pages in memory should be disabled,

unless enabled for a specific reason

Memory Deduplication OptionsGreat for OS memoryDoesn’t work at all for SQL Server

Unless… multiple SQL Servers have the same pages in cache

Storage Configuration OptionsIO is the same if the disks are physical or

virtualUse automatic tier adjusting technology if

possibleOn EMC Arrays – FASTDell Compellent Arrays

Keep OS, data, logs, tempdb on separate disks if possible

Storage DeduplicationCan greatly improve overall performanceBy deduplicating OS virtual disks, we save

much less data to the arrayAs less data is written to the array, less OS

data is loaded into cache on the array

PitfallsShared CPUShared MemorySlow Disk Access timesAnother layer of ManagementStorage Path Flooding

Deciding FactorsDisk IO

IO Per SecondsCPU Load

CPU UsageCore CountsProcessor Queuing

Memory Usage

Virtualization LimitsBy default vMotion or Instant Failover

requires hosts have like CPUs models and matching instruction sets

Hyper-V doesn’t include memory de-duplicationIt does now, introduced in Windows 2008 R2

SP1

Management ToolsVMware requires vCenter to manage a clusterHyper-V has basic management tools included, including

integration with Windows Failover Cluster ManagerSystem Center Virtual Machine Manager (SCVMM) is

strongly recommended for managing Production EnvironmentsSCVMM can also manage ESX 3.5 or vSphere 4.0 Servers

(requires vCenter server)SCVMM integrates with System Center Operations

Manager (SCOM) to drive SCVMM Performance Resource Optimization (PRO Tips)

SCVMM is required for Hyper-V Physical to Virtual (P2V) migrations.

vCenter Client

LicensingCAL based licensing doesn’t change

1 Server license per guest + CALs for usersCPU licensing

1 license for physical CPU used1 2008 R2 DCE CPU license for each CPU in

hostIf you have SQL 2008 R1 with SA for hosts you

are grandfathered into SQL 2008 R2. http://bit.ly/cGiatM

Each guest needs a Windows license

Monitoring Hosts

Monitoring Hosts

Monitoring the GuestGuest CPU Load requires double checking

against the hostDisk IO rates are accurateDisk IO throughput should be confirmed with

the hostDisk Latency should be confirmed with the

host

Monitoring the Guest

Monitoring the Guest

Denny Cherrymrdenny@mrdenny.com

http://www.mrdenny.com