Oracle VM and Microsoft Windows

Oracle VM and Microsoft Windows [ID 468634.1]
Modified 07-FEB-2011 Type BULLETIN Status PUBLISHED
In this Document
Purpose
Scope and Application
Oracle VM and Microsoft Windows
References

Applies to:

Oracle VM - Version: 2.1 to 2.2.1 [Release: OVM21 to OVM221]
Generic Windows
Purpose

This document is to provide technical information about Microsoft Windows operating systems and Oracle VM.
Scope and Application

This document is about Oracle VM and Windows operating systems for IT professionals that are planning to work / working on respective configurations.
Oracle VM and Microsoft Windows

Oracle VM supports Microsoft Windows as a guest OS with certain limitations:
Only
Windows™ 2000
Windows™ 2003
Windows™ XP Professional
Windows™ Vista
Microsoft Windows™ 2008 Service Pack 1 (on Oracle VM 2.2 or higher)
32- and 64- bit
For more recent information of Oracle VM 2.1 see Oracle® VM Server User's Guide Release 2.1 Part Number E10898-01 Table 4-3
For more recent information of Oracle VM 2.2 see Oracle® VM Server Release Notes Release 2.2
Only on HV capable hardware (i.e. only with HVM, or simply on CPUs with INTEL-VM support or AMD-V support). See Note 468463.1
As Oracle VM server is installed on bare hardware it cannot be installed on Windows. Oracle VM should not be compared to VMWare Workstation or alike.
Oracle VM supports para- and full-virtualization. Generally para-virtualization is faster than full virtualization due to series of reasons:
Hardware assisted full virtualization is done via an abstraction layer and with some specific instructions at the CPU level
The virtualization code for HV is more complex than para-virtualization and therefore puts some overhead (even though the INTEL-VT or AMD-V simplifies the code to some extent)
Paravirtualization provides performance features like:
Simpler Virtual Machine Monitor
Stronger resource isolation
Data is transferred using asynchronous I/O rings.
An event mechanism replaces hardware interrupts for notifications
Intelligent NIC with DMA-based packet transfer (without any HW support)
etc.
For para-virtualization the O/S kernel needs to be modified and this was directly provided Linux as it is open source and todays OEL/RHEL has this support already.

The Windows OS has hardware specific code in the kernel so it is generally to take more resources to be ported to be enabled for para-virtualization.

From paper "Xen and the Art of Virtualization":

OS Subsection
# lines Linux
# lines XP
Architecture-independent
78
1299
Virtual network driver
484
-
Virtual block-device driver
1070
-
Xen-specific (non-driver)
1363
3321
Total
2995
4620
(Portion of total x86 code base
1.36%
0.04% )

Table 2: The simplicity of porting commodity OSes to Xen. The cost metric is the number of lines of reasonably commented and formatted code which are modified or added compared with the original x86 code base (excluding device drivers).

Moreover as Windows kernel is proprietary the porting/modification is to be done by Microsoft.

Still Windows can be run in full-virtualized mode (using Intel-VT or AMD-V features) but it is generally slower than para-virtualization due to reasons described above.

Oracle VM Windows Paravirtual (PV) Drivers for Microsoft Windows Guests (XP/Vista/7/2003/2008/2008 R2) 2.0.7 - 32-bit/64-bit (signed by Microsoft for the Windows Logo Program for Windows 2008 and Windows 2008 R2) are available from the Oracle edelivery site for customers in the Oracle VM 2.2.1 media pack selection.

The drivers are listed as certified by Microsoft on the Microsoft Server Catalog.

For more information please see the referenced material below.
References