Virtualization in Windows
Server 2008 R2
Arlindo Alves
Microsoft
http://blogs.technet.com/aralves

Sponsors

Agenda
• Hyper-V V2
• Cluster Shared Volumes
• Live Migration
• Hosted Desktops

Architecture

Hyper-V Architecture
Parent Partition
User
Mode
Kernel
Mode
Ring -1

Hyper-V Architecture

Hyper-V
Capabilities
• 32-bit (x86) & 64-bit (x64) VMs
• Large memory support (64 GB) per VM
• SMP VMs (up to 4 cores)
• Integrated cluster support for HA & Quick Migration
• BitLocker: Seamless, secure data encryption
• Live Backup: Volume Shadow Service integration
• Pass-through disk access for VMs
• Virtual Machine snapshots
• New hardware sharing architecture (VSP/VSC/VMBus)
• Disk, networking, input, video
• Robust networking: VLANs and NLB
• DMTF standard for WMI management interface
• Support for Full or Server Core installations

Windows Server 2008 R2 Hyper-V
• Building on the rock-solid architecture of Windows
Server 2008 Hyper-V
• Integration with new technologies
• Enabling new dynamic scenarios:
• Increased Server Consolidation
• Dynamic Data Center
• Virtualized Centralized Desktop
• Customer Driven

Live Migration

Live Migration
• #1 Customer Request
• Moving a virtual machine from one server to
another without loss of service
• Workload is unaware of the migration
• Maintain TCP connections of the guest OS
• Enables new dynamic scenarios
• No downtime host servicing
• Maintenance Mode with SCVMM R2
• Load Balancing with SCVMM R2 & PRO

Live Migration
• Live Migration via Cluster Manager
• In box UI
• Live Migration via Virtual Machine Manager
• Orchestrate migrations via policy
• Moving from Quick to Live Migration:
• Guest OS limitations?: No
• Changes to VMs needed?: No
• Changes to storage infrastructure: No
• Changes to network infrastructure: No
• Update to Windows Server 2008 R2
Hyper-V: Yes

Live Migration
Initiate Migration
I want to Migrate
this VM to another
physical machine
Client accessing VM
SAN
• IT Admin initiates a Live
Migration to
move a VM from one
VHD
host to another

Live Migration
Memory Copy: Full Copy
Memory content is
copied to new server
VM pre-staged
SAN
• First initial copy is of all
in memory content
VHD

Live Migration
Memory Copy: Dirty Pages
Client continues
accessing VM
Pages are
being dirtied
SAN
• Client continues to access
VM, which results in
memory being modified
VHD

Live Migration
Memory Copy: Incremental Copy
Recopy of changes
Smaller set of
changes
• Hyper-V tracks changed SAN
data, and re-copies over
incremental changes
• Subsequent passes get faster
as data set is smaller VHD

Live Migration
Final Transition
Partition State
copied
VM Paused
SAN
• Window is very small
and within TCP
connection timeout VHD

Live Migration
Post-Transition: Clean-up
Client directed to
new host
Old VM deleted once
migration is verified
successful
• ARP issued to have routing SAN
devices update their tables
• Since session state is
maintained, no reconnections
necessary VHD

DEMO
• Live Migration
Demo

Migration & Storage
• Windows Server 2008 R2 Hyper-V
• NEW Cluster Shared Volume (CSV)
• CSV provides a single consistent file name space;
• All Windows Server 2008 R2 servers see
the same storage
• Easy setup; Uses NTFS
• No reformatting SANs
• Create one big data store
• No more drive letter problems
• Existing tools just work

Cluster Shared Volumes
• All servers “see” the same storage

Clustering VMs with CSV
1. Install Failover Clustering, Hyper-V from 2008 R2
2. Create & Validate your cluster
3. Enable CSV
4. Add storage to CSV
5. Copy VHD file to CSV storage
C:\\ClusterStorage\\...
6. Create VM, select CSV Path for VM and files
7. Add the VM to the cluster making it HA
8. Within the VM, configure your application

Individual VM Failover on a LUN
Disk
Resource
Disk
Resource
SAN
Same LUN
Solution
Today VHD 1 VHD 2 VHD 3

Individual VM Failover on a LUN
VMs running
on Node 1 are
unaffected
SAN
Coordinator
Node
Same LUN
The Solution
(R2) VHD 1 VHD 2 VHD 3

Optimized Capacity Planning
• In the past (2008) - 1 LUN for 1 VM
• LUN smallest unit of failover
• Run out of storage space Free Space
• Wasted storage space
VHD
Used VHD
• Storage management challenging
Space
Wasted Out of
Space Space
VHD VHD VHD
VHD VHD VHD VHD
VHD VHD VHD VHD VHD VHD
Many LUNs to Manage

Optimized Capacity Planning
• The Solution (R2): 1 LUN for many VMs
• VM smallest unit of failover
• VMs share the pool of unused space
• Flexible utilization and easy Free Space
management Used VHD
VHD
Space
VHD
VHD VHD VHD
VHD VHD
Free Space
VHD VHD VHD VHD

DEMO
• Clustered Shared
Volumes

Live Migration Best Practices
• Cluster Shared Volumes
• Not required but, highly recommended
• Network Adapters
• Cluster Heartbeat/Management
• CSV
• Virtual Switches
• iSCSI
• MPIO: Add another
• Live Migration & IPSEC
• Will impact migration performance

New Processor Feature Support
Microsoft Confidential

VM Memory Management
• Today, processors provide one level of
address translation, but hypervisor
needs to manage two
Guest Virtual Guest Virtual
Guest OS Address Address
Shadow page
defines GVA-to- tables combine
GPA mappings these mappings
Guest Physical because the
Address processor knows
Hypervisor how to perform
defines GPA-to- only one level of
SPA mappings System System translation
Physical Physical
Address Address

Shadow Page Tables
• Hypervisor maintains a Shadow Page Table
• Combines two layers of translation into a
single page table
• Demand-filled when Child OS touches a page
• Flushed any time the Child OS modifies
its page tables
• Shadow Page Table overhead
• Fills and flushes invoke the hypervisor
• Can account for up to 10% of total CPU time
• Consumes roughly 1MB of memory per VM

Second Level
Address Translation (SLAT)
• Goes by several names
• Intel: Extended Page Tables (EPT)
• AMD: Nested Page Tables (NPT)/Rapid Virtualization Indexing (RVI)
• Processor provides two levels of translation
• Walks the guest OS page tables directly
• No need to maintain Shadow Page Table
• No hypervisor code for demand-fill or flush operations
• Resource savings
• Hypervisor CPU time drops to 2%
• Roughly 1MB of memory saved per VM
• Benefits Large Memory Workloads
• Exchange, SQL, Terminal Services

Windows Server 2008 R2
Core Parking
• Overview
• Scheduling virtual machines on a single server for
density as opposed to dispersion
• This allows “park/sleep” cores by putting them in
deep C states
• Benefits
• Enhances Green IT by reducing
CPU power consumption

Windows Server 2008
16 LP Server

Windows Server 2008 R2 Core Parking
16 LP Server

Hyper-V Virtual Storage

Hot Add/Remove Storage
• Overview
• Add and remove VHD and pass-through disks to a
running VM without requiring a reboot.
• Hot-add/remove disk applies to VHDs and pass-through
disks attached to the virtual SCSI controller
• Benefits
• Enables storage growth in VMs without downtime
• Enables additional datacenter backup scenarios
• Enables new SQL/Exchange scenarios

Performance
• Major Performance Improvements
• Dynamic Virtual Hard Disks
• 64k Sequential Writes: 3x Faster
• 4k Random Writes
• 15x Faster
• 85% of Native
• Fixed Disks
• Hyper-V R1: 94% of native
• Hyper-V R2: Almost Equal to native

Hyper-V Networking

TCP Offload Support
• Overview
• TCP/IP traffic in a VM can be offloaded to a
physical NIC on the host computer.
• Benefits
• Reduce CPU burden
• Networking offload to improve performance
• Live Migration is supported with Full TCP Offload
• Major performance improvement on 10 Gb/E

Virtual Machine Queue
(VMQ)
• Overview
• NIC can DMA packets directly into VM memory
• VM Device buffer gets assigned to one of the queues
• Avoids packet copies in the VSP
• Avoids route lookup in the virtual switch (VMQ Queue ID)
• Allows the NIC to essentially appear as multiple NICs
on the physical host (queues)
• Benefits
• Host no longer has device DMA data in its own buffer
resulting in a shorter path length for I/O (performance
gain)

Jumbo Frames
• Jumbo Frame Support
• Ethernet frames >1,500
bytes
• Ad hoc standard is ~9k
• Overview
• Enables 6x larger
payload per packet
• Benefits
• Reduce CPU utilization of
large file transfers
• Reduces TCP/IP overhead
by up to 84%

Microsoft Hyper-V Server 2008 R2
Microsoft Confidential

Microsoft Hyper-V Server V2
New Features
• Live Migration
• High Availability
• New Processor Support
• Second Level Address Translation
• Core Parking
• Networking Enhancements
• TCP/IP Offload Support
• VMQ & Jumbo Frame Support
• Hot Add/Remove virtual storage
• Enhanced scalability
• Enhancements to SCONFIG

Hyper-V Server R1 vs. R2
Microsoft Hyper-V Server Microsoft Hyper-V Server
2008 R2
Processor Support Up to 4 processors Up to 8 processors
up to 24 LPs Up to 32 LPs
Physical Memory Support Up to 32 GB Up to 1 TB
Virtual Machine Memory Up to 32 GB total 64 GB of memory per VM
Support (e.g. 31 1 GB VMs or
5 6 GB VMs)
Live Migration No Yes
High Availability No Yes
Management Options Free Hyper-V Manager Free Hyper-V Manager
MMC MMC
SCVMM SCVMM R2

Hosted Desktops

Terminal Services
Virtualization
• Overview
• TSV - Virtualized “Centralized Desktop” provisioning,
access and management solution on top of Hyper-V
• Unified user and admin experience for traditional TS
(session per user) and TSV (VM per user).
• Deployment Scenarios
• Temporary (until Logoff) VM per user Assignment
• Permanent VM per user assignment
• Built-in solution for low complexity deployments
• Features and management are tuned for Entry Level
deployments. Example: 4 TS/TSVM Servers with few apps.

Connection Broker Infrastructure
TS Gateway
TS Session Broker
TS Users
Remote
TS Farm
Storage
Hosted Desktop
Users (Remote)
Hyper-V Farm
Hosted Desktop Users TS Users

Virtualization Management
“Virtualization without good management
is more dangerous than not using
virtualization in the first place.”
– TOM BITTMAN, GARTNER VP AND ANALYST, 9 MAY, 2007
Virtualization Will Drive Major Change in IT Infrastructure and Operations in the Next Three Years, Tom Bittman, May 8, 2007

Managing The Server Lifecycle

Virtual Machine Manager 2008
A centralized, heterogeneous management solution for the virtual datacenter
• Centralized virtual machine deployment and
management for Hyper-V, Virtual Server, and
VMware ESX servers
• Intelligent placement of Virtual Machines
• Fast and reliable P2V and V2V conversion
• Comprehensive application and service-level
monitoring with Operations Manager
• Integrated Performance and Resource
Optmization (PRO)
• Increase Agility
• Rapid provisioning of new and virtual machines
with templates

OPATIJA | 20 – 24.4. 2009.
Thank you!