The values of server virtualization are well understood today. Customers implement
server virtualization to increase server utilization, handle peak loads efficiently,
decrease total cost of ownership (TCO), and streamline server landscapes.
Similarly, storage virtualization helps to address the same challenges as server
virtualization. Storage virtualization also expands beyond the boundaries of physical
resources and helps to control how IT infrastructures adjust to rapidly changing
business demands. Storage virtualization benefits customers through improved
physical resource utilization and improved hardware efficiency, as well as reduced
power and cooling expenses. In addition, consolidation of resources obtained
through virtualization offers measurable returns on investment for today’s
businesses. Finally, virtualization serves as one of the key enablers of cloud
solutions, which are designed to deliver services economically and on demand.
VMware vSphere 5 and IBM XIV Gen3 end-to-end virtualization lab report
1. VMware vSphere 5 and
IBM XIV Gen3 end-to-end
virtualization
Lab report: vSphere 5, vMotion, HA, SDRS,
I/O Control, vCenter, VAAI and VASA
IBM Corporation 2011 1|Page
2. Contents
1. Executive summary .............................................................................................................. 4
2. Introduction ............................................................................................................................ 5
2.1. VMware vSphere 5 features and benefits ................................................................. 5
2.2. Introduction to new XIV Gen3 features ...................................................................... 6
2.3. Testing goals .................................................................................................................. 7
2.4. Description of the equipment....................................................................................... 7
3. Test structure......................................................................................................................... 7
3.1. Hardware setup.............................................................................................................. 7
3.1.2. ISCSI configuration..............................................................................................................8
3.1.3. VMware vSphere..................................................................................................................8
3.2. VMware 5.0 environment Software setup installation.............................................. 8
3.2.1. VMware 5.0 Configuration ..................................................................................................8
3.2.2. VM OS software ...................................................................................................................8
3.2.3. Testing software...................................................................................................................9
4. Test procedures .................................................................................................................... 9
4.1. Iometer for performance testing .................................................................................. 9
4.1.1. Disk and network controller performance.........................................................................9
4.1.2. Bandwidth and latency capabilities of buses...................................................................9
4.2. vSphere vMotion.......................................................................................................... 10
4.2.1. vSphere vMotion - Transfer time of VMs to a local disk (DAS) ..................................10
4.2.2. vSphere vMotion - Transfer times of VMs to XIV LUN (SAN).....................................10
4.3. vSphere High Availability............................................................................................ 11
4.5. Profile-Driven Storage ................................................................................................ 13
4.6. vSphere Storage I/O Control ..................................................................................... 14
4.7. vCenter.......................................................................................................................... 15
4.8. VMware vSphere Storage API Program .................................................................. 15
4.8.1. vSphere Storage APIs for Array Integration (VAAI) .....................................................15
• Full copy, Hardware-Assisted Locking, and Block Zeroing .........................................16
4.8.2. vStorage APIs for Storage Awareness (VASA).............................................................19
IBM Corporation 2011 2|Page
3. 5. Conclusion ........................................................................................................................... 20
Appendix A (Iometer for performance testing) ...................................................................... 22
Appendix B (vSphere vMotion) ................................................................................................ 47
Appendix C (Transfer times of VMs to XIV LUNs (SAN))................................................... 51
Appendix D ( vSphere High Availability)................................................................................. 55
Appendix E (vSphere Storage DRS)....................................................................................... 59
Appendix F (Profile-Driven Storage) ....................................................................................... 75
Appendix G (Storage I/O Control) ........................................................................................... 90
Trademarks and special notices ............................................................................................ 101
IBM Corporation 2011 3|Page
4. 1. Executive summary
The values of server virtualization are well understood today. Customers implement
server virtualization to increase server utilization, handle peak loads efficiently,
decrease total cost of ownership (TCO), and streamline server landscapes.
Similarly, storage virtualization helps to address the same challenges as server
virtualization. Storage virtualization also expands beyond the boundaries of physical
resources and helps to control how IT infrastructures adjust to rapidly changing
business demands. Storage virtualization benefits customers through improved
physical resource utilization and improved hardware efficiency, as well as reduced
power and cooling expenses. In addition, consolidation of resources obtained
through virtualization offers measurable returns on investment for today’s
businesses. Finally, virtualization serves as one of the key enablers of cloud
solutions, which are designed to deliver services economically and on demand.
The features of VMware vSphere 5.0 and IBM XIV® Gen3 storage together build a
powerful end to end virtualized infrastructure, covering not only servers and storage,
but also end-to-end infrastructure management, leading to more-efficient and higher-
performing applications.
VMware is a leading manufacturer of virtualization software. VMware vSphere 5 is
the first version of VMware vSphere built exclusively on ESXi, a hypervisor purpose-
built for virtualization that runs independently from a general purpose operating
system. With an ultra-thin architecture, ESXi delivers industry-leading performance,
reliability and scalability all within a footprint of less than 100 MB. The result is
streamlined deployment and configuration as well as simplified patching, updating
and better security.
The IBM XIV Storage System Gen3 uses an advanced storage fabric architecture
built for today’s dynamic data centers with an eye towards tomorrow. With industry
leading storage software and a high-speed InifiniBand fabric, the XIV Gen3 delivers
storage features and performance demanded in VMware infrastructures including:
• Automation and simplicity
• Multi-level integration with vSphere
• Centralized management in vCenter
• vStorage APIs for Array Integration (VAAI)
• vStorage APIs for Storage Awareness integration (VASA)
• Storage Replication Adapter (SRA) for Site Recovery Manager (SRM)
• Engineering-level collaboration for vSphere 5, and beyond
A global partnership with IBM and VMware coupled with the forward thinking
architecture of IBM XIV Gen3 Storage System provide a solid foundation for virtual
infrastructures today and into the future. On top of this solid foundation, VMware
vSphere 5.0 and IBM XIV Gen3 complement each other to create a strong
virtualization environment. Evidence of how seamlessly these features work together
IBM Corporation 2011 4|Page
5. to provide this powerful virtualized environment are found in the following sections.
Testing details can be found in Appendices A through G.
2. Introduction
2.1. VMware vSphere 5 features and benefits
Enhancements and new features in VMware vSphere 5 are designed to
help deliver improved application performance and availability for all
business-critical applications. VMware vSphere 5 introduces advanced
automation capabilities including:
• Four times larger virtual machines (VMs) scale to support any
application. With VMware vSphere 5, VMware helps make it easier for
customers to virtualize. VMware vSphere 5 is capable of running VMs
four times more powerful than VMware vSphere 4, supporting up to 1
terabyte of memory and up to 32 virtual processors. These VMs are able
to process in excess of 1 million I/O operations per second, helping
surpass current requirements of the most resource-intensive applications.
For example, VMware vSphere 5 is able to support a database that
processes more than two billion transactions per day.
• Updates to vSphere High Availability (HA) offer reliable protection
against unplanned downtime. VMware vSphere 5 features a new HA
architecture that is easier to set up than with the previous vSphere 4.1
release (customers can get their applications set up with HA in minutes),
is more scalable, and offers availability guarantees.
• Intelligent Policy Management: Three new automation
advancements deliver cloud agility. VMware vSphere 5 introduces
three new features that automate datacenter resource management to
help IT respond to the business faster while reducing operating expenses.
These features deliver intelligent policy management: A “set it and forget
it” approach to data center resource management. Customers define the
policy and establish the operating parameters, and VMware vSphere 5
does the rest. VMware vSphere 5 intelligent policy management features
include:
• Auto-Deploy enables automatic server deployment “on the fly” and
e.g. reduces the time that it takes to deploy a non-virtualized data
center with 40 servers from 20 hours to 10 minutes. After the servers
are up and running, Auto-Deploy also automates the patching
process, making it possible to instantly apply patches to many servers
at once.
• Profile-Driven Storage reduces the number of steps required to
select storage resources by grouping storage according to user-
defined policies (for example, gold, silver, bronze, and so on). During
the provisioning process, customers simply select a level of service
for the VM, and VMware vSphere automatically uses the storage
resources that best align with that level of service.
• Storage Distributed Resource Scheduler (DRS) extends the
automated load-balancing capabilities that VMware first introduced in
IBM Corporation 2011 5|Page
6. 2006 with DRS to include storage characteristics. After a customer
has set the storage policy of a VM, Storage DRS automatically
manages the placement and balancing of the VM across storage
resources. By automating the ongoing resource allocations, Storage
DRS eliminates the need for IT to monitor or intervene, while ensuring
the VM maintains the service level defined by its policy.
2.2. Introduction to new XIV Gen3 features
The XIV Storage System has received rapid market success with thousands of
installations in diverse industries worldwide, including financial services,
healthcare, energy, education and manufacturing. IBM XIV integrates easily with
virtualization, email, database, analytics and data protection solutions from IBM,
SAP, Oracle, SAS, VMware, Symantec and others.
The XIV Gen3 model exemplifies the XIV series’ evolutionary capability: Each
hardware component has been upgraded with the latest technologies, while the
core of the architecture remains intact. The XIV Gen3 model gives applications a
tremendous performance boost, helping customers meet increasing demands
with fewer servers and networks.
The XIV Storage System series common features enable it to:
• Self-tune and deliver consistently high performance with automated
balanced data placement across all key system resources, eliminating hot
spots
• Provide unprecedented data protection and availability through active-
active N+1 redundancy of system components and rapid self-healing (<
60 minutes for 2 TB drives)
• Enables unmatched ease of management through automated tasks and
an intuitive user interface
• Help promote low TCO enabled by high-density disks and optimal
utilization
• Offer seamless and easy-to-use integrated application solutions with the
leading host platforms and business applications
XIV Gen3 adds ultra-performance capabilities to the XIV series compared to its
previous generation by providing:
• Up to 4 times the throughput, cutting time and boosting performance for
business intelligence, archiving and other extremely demanding
applications
• Up to 3 times speedier response time, enabling faster transaction
processing and greater scalability with online transaction processing
(OLTP), database and email applications
• Power to serve even more applications from a single system with a
comprehensive hardware upgrade that includes InfiniBand inter-module
connect, larger cache, faster disk controllers, increased processing
power, and more fibre-channel (FC) and iSCSI connectivity.
• Option for future upgradeability to solid-state drive (SSD) caching for
breakthrough SSD performance levels at a fraction of typical SSD storage
costs, combined with very high-density drives helping achieve even lower
TCO.
IBM Corporation 2011 6|Page
7. 2.3. Testing goals
The purpose of the following test cases is to show that VMware vSphere 5 and
the IBM XIV Storage System Gen3 storage solution seamlessly complement
each other as an efficient storage virtualization solution.
The testing in this paper is for proof of concept and should not be used as a
performance statement.
2.4. Description of the equipment
The test setup utilizes the following IBM equipment:
• (3) IBM System x® 3650 M3 servers
• (2) IBM System Storage® SAN24B-4 Express switches
• (3) Qlogic QLE2562 HBAs
• IBM XIV Storage System Gen3 series hardware, Firmware Version 11.0
3. Test structure
3.1. Hardware setup
Figure 1 shows the vSphere 5.0 system x and XIV reference architecture
diagram.
IBM Corporation 2011 7|Page
8. Ether
Et
Et
he
FC
he
FC
FC
rn FC
FC
FC
et
rn
ne
et
t
FC
FC
Figure 1. vSphere 5.0 System x and XIV reference architecture diagram
Fibre Channel configuration
• (3) IBM x3650 M3 servers
• (2) SAN24B-4 Express (8GB) (SAN A and SAN B)
• (3) Qlogic QLE2562 HBAs (8GB)
3.1.2. ISCSI configuration
• (2) IBM x3650 M3 servers
• 1 GB Ethernet Switch
3.1.3. VMware vSphere
• (1) VMware vSphere VM (Microsoft® Windows® 2008 R2)
3.2. VMware 5.0 environment Software setup installation
3.2.1. VMware 5.0 Configuration
• VMware 5.0 Enterprise Plus
3.2.2. VM OS software
• Windows 2008 R2
• Linux rhel 6.0
IBM Corporation 2011 8|Page
9. 3.2.3. Testing software
Iometer for I/O testing
Note: Iometer is downloaded from www.iometer.org and distributed under
the terms of the Intel Open Source License. The iomtr_kstat kernel
modules, as well as other future independent components, are distributed
under the terms of the GNU Public License)
4. Test procedures
4.1. Iometer for performance testing
When implementing storage, whether the storage is directly attached to a server
(direct-attach storage or DAS), connected to a file-based network (network-
attached storage or NAS), or resides on its own dedicated storage network
(storage area network or SAN — Fibre Channel or iSCSI), it is important to
understand storage performance. Without this information, managing growth
becomes difficult. Iometer can help deliver this critical performance data to help
you make better decisions about the storage needed or whether the current
storage solution can handle an increased load.
4.1.1. Disk and network controller performance
The following two tests show the possible throughput of a three-VM setup
and the IBM XIV Gen3 storage array configuration without any special
tuning. See “Appendix A (Iometer for performance testing)” for test
procedures.
Test object Performance of disk and network controllers.
Setup (3) VMs, (1) processor, 4 GB memory, (3) 40GB XIV LUNs for
test
Test steps Install Windows 2008 R2
Install Iometer
Set up test with Iometer 40 Workers
8k block size, 30% write and 70% reads
Run-time 1 hour
See “Appendix A (Iometer for performance testing)”
Results VM (1) 76737 IOPS
VM (2) 77296 IOPS
VM (3) 72248 IOPS
Test notes *This is not a performance measurement test.
4.1.2.Bandwidth and latency capabilities of buses
Test object Bandwidth and latency capabilities of buses
Setup (3) VMs (1) processor 4 GB memory (3) 40GB XIV LUNs for
test
Test Steps Install Windows 2008 r2
Install Iometer
Set up test with Iometer 40 Workers
IBM Corporation 2011 9|Page
10. 8k block size, 30% write and 70% reads
Run-time 1 hour
See “Appendix A (Iometer for performance testing)”
Results VM (1) 588 Mbps, 0.4641 ms average latency
VM (2) 603 Mbps, 0.0257 ms average latency
VM (3) 565 Mbps, 0.8856 ms average latency
Test notes *This is not a performance measurement test.
The Iometer testing shows that the IBM XIV Gen3 performed
exceptionally well with 70000+ IOPS range with a latency well below the 1
ms range. Figure 2 shows the Iometer measured performance results for
VM1.
Figure 2. Iometer VM1 results for 40 workers
4.2. vSphere vMotion
VMware vSphere vMotion technology enables live migration of VMs from server
to server.
This test demonstrates the difference in transfer times between moving VMs
between local server disks (DAS) and moving VMs to the IBM XIV Gen3 (SAN).
This demonstration also shows that the XIV Gen3 can move data at computer
bus speeds.
4.2.1.vSphere vMotion - Transfer time of VMs to a local disk (DAS)
Test object Transfer time of VMs to local disk
Setup VM Size 14.44 GB
Test steps See “Appendix B (vSphere vMotion)”
Results 10 min 3 seconds
Test notes None
4.2.2. vSphere vMotion - Transfer times of VMs to XIV LUN (SAN)
Test Object Transfer time of VMs to XIV LUN
IBM Corporation 2011 10 | P a g e
11. Setup VM Size 14.44 GB
Test steps See “Appendix C (Transfer times of VMs to XIV LUNs (SAN)))”
Results 1 minute 31 seconds
Test notes None
Overall test results: For the two tested VMs, transferring all data from the server
to XIV was 6.7x faster than from the server to the local disk for the tested
configuration, demonstrating the synergy between XIV and vSphere vMotion.
See “Appendix B (vSphere vMotion)” and “Appendix C (Transfer times of VMs to
XIV LUNs (SAN))” for test details.
4.3. vSphere High Availability
The vSphere High Availability (HA) feature delivers reliability and
dependability needed by many applications running on virtual machines,
independent of the operating system and applications running within it. vSphere
HA provides uniform, cost-effective failover protection against hardware and
operating system failures within VMware virtualized IT environments.
Test object Failover of an ESX server
Setup See “Appendix D ( vSphere High Availability)”
Test steps See “Appendix D ( vSphere High Availability)”
Results When encountering a test-induced failure, the host moved to a
new ESXI host and the storage seamlessly moved with it.
Test notes none
This test shows that the High Availability feature works seamlessly with the IBM
XIV Gen3 as the test results show how a failure automatically moves the VM to a
new ESXI host and the storage seamlessly moves with it as shown in Figure 3.
See “Appendix D ( vSphere High Availability)” for test details.
IBM Corporation 2011 11 | P a g e
12. Figure 3. Demonstrating HA feature: VM moves to new ESXI host along with storage
4.4. vSphere Storage Distributed Resource Scheduler
The vSphere Storage Distributed Resource Scheduler (SDRS) aggregates
storage resources from several storage volumes into a single pool and simplifies
storage management. Intelligently placing workloads on storage volumes during
provisioning based on the available storage resources, SDRS performs ongoing
load balancing between volumes to ensure space and I/O bottlenecks are
avoided as per predefined rules that reflect business needs and changing
priorities.
Test object Testing aggregated storage resources of several storage
volumes.
Setup
Test steps See “Appendix E (vSphere Storage DRS)”
Results Passed, storage bottle neck avoided
Test notes None
When run without SDRS, a storage bottleneck occurs. When SDRS is running,
the system performs a task to load balance the disk. An imbalance on the
datastore triggers the Storage DRS recommendation to migrate a virtual
machine. Storage DRS makes multiple recommendations to solve this datastore
imbalance. See “Appendix E (vSphere Storage DRS)” for test details.
IBM Corporation 2011 12 | P a g e
13. Figure 4. Storage DRS recommendations solve a datastore imbalance.
4.5. Profile-Driven Storage
Profile-Driven Storage enables easy and accurate selection of the correct
datastore on which to deploy VMs. The selection of the datastore is based on the
capabilities of that datastore. Then, throughout the lifecycle of the VM, a
database administrator (DBA) can manually check to ensure that the underlying
storage is still compatible, that is, it has the correct capabilities. This means that
if the VM is cold-migrated or migrated using Storage vMotion, administrators can
ensure that the VM moves to storage that meets the same characteristics and
requirements of the original source “profile.” If the VM is moved without checking
the capabilities of the destination storage, the compliance of the VM's physical
storage characteristics can still be checked from the User Interface at any time,
and the administrator can take corrective actions if the VM is no longer on a
datastore which meets its storage requirements.
Test object Deploying VMs on Profile-Driven Storage
Setup
Test steps See “Appendix F (Profile-Driven Storage)”
Result This test demonstrates that with Profile Driven Storage, a user
is able to ensure physical storage characteristics are consistent
between migrations of a VM
Test notes
This test shows that the Profile-Driven Storage feature works with IBM XIV Gen3
to help ensure VM storage profiles meet requirements as shown in Figures 5 and
6. See “Appendix F (Profile-Driven Storage)” for test details.
IBM Corporation 2011 13 | P a g e
14. Figure 5. The VM storage profile is now compliant.
Figure 6. VM storage profile
4.6. vSphere Storage I/O Control
VMware vSphere 5.0 extends Storage I/O Control to provide cluster-wide I/O
sharing and limits for datastores. This feature helps ensure that no single virtual
machine should be able to create a bottleneck in any IT environment regardless
of the type of shared storage used. Storage I/O Control automatically throttles a
VM that is consuming a disparate amount of I/O bandwidth when the configured
latency threshold has been exceeded. This enables other virtual machines using
the same datastore to receive their fair share of I/O performance. Storage DRS
and Storage I/O Control work together to prevent deprecation of service-level
agreements while providing long- term and short-term I/O distribution balance.
Test object Test cluster-wide I/O sharing and limits for datastores
Setup
Test steps See “Appendix G (Storage I/O Control)” for test details
IBM Corporation 2011 14 | P a g e
15. Results Observed a gradual increase in the IOPS for the VM with 2000
shares and a gradual decrease in IOPS for the VM with 1000
shares.
The test results showed that more resources needed to be
Test notes allocated to one VM to balance the workload. VMware throttled
the I/O of the higher IOPS VM to give more I/O to the slower
VM.
This test shows that the Storage I/O Control feature works within VMware 5.0
with no changes to the IBM XIV Gen3. See “Appendix G (Storage I/O Control)”
for test details.
4.7. vCenter
VMware vCenter Server is a tool that manages multiple host servers that run
VMs. It enables the provisioning of new server VMs, the migration of VMs
between host servers and the creation of a library of standardized VMs
templates. You can install plug-ins to add several other features, for example,
VASA for discovery of storage topology and capability, event and alert status;
SRM for disaster recovery automation exploiting storage business-continuity
features.
4.8. VMware vSphere Storage API Program
VMware vSphere provides an API and software development kit (SDK)
environment to allow customers and independent software vendors to enhance
and extend the functionality and control of vSphere. VMware has created several
storage virtualization APIs that help address storage functionality and control.
4.8.1. vSphere Storage APIs for Array Integration (VAAI)
Virtualization administrators look for ways to improve scalability,
performance, and efficiency of their vSphere infrastructure. One way is by
utilizing storage integration with VMware vStorage APIs for Array Integration
VAAI. VAAI is a set of APIs or primitives that allow vSphere infrastructures
to offload processing of data-related tasks, which can burden a VMware
ESX server. Utilizing a storage platform like XIV with VAAI
enabled, can provide significant improvements in vSphere
performance, scalability, and availability. This capability was initially a
private API requiring a plug-in in vSphere v4.1, but with vSphere 5.0, it is
now a T10 SCSI standard.
The VAAI driver for XIV enables the following primitives:
• Full copy (also known as hardware copy offload):
o Benefit: Considerable boost in system performance and fast
completion of copy operations; minimizes host processing
and network traffic
• Hardware-assisted locking (also known as atomic test and set):
Replacement of the SCSI-2 lock/reservation in Virtual Machine File
System (VMFS)
o Benefit: Significantly improves scalability and performance
IBM Corporation 2011 15 | P a g e
16. • Block zeroing (also known as write same)
o Benefit: Reduces the amount of processor effort, and
input/output operations per second (IOPS) required to write
zeroes across an entire EagerZeroedThick (EZT) Virtual
Machine Disk (VMDK)
The XIV Storage System now provides full support for VAAI. The following
sections describe each of these primitives.
• Full copy
Tasks such as VM provisioning and VM migration are part of everyday
activities of most VMware administrators. As the virtual environment
continues to scale, it is important to monitor the overall impact that these
activities have on the VMware infrastructure.
Toggle the hardware assisted copy by changing the
DataMover.HardwareAcceleratedMove parameter in the Advanced
Settings tab in vSphere Virtual Center (set to 1 to enable, 0 to disable).
When the value for hardware acceleration is 1, the data path changes for
tasks such as Storage vMotion, as illustrated in Figure 7.
ction
tion
opy
Data
tr u c
ta C
Instru
Cop
Ins
Da
y
Figure 7: VAAI Full copy primitive
In this instance, the ESX server is removed from the data path of the data
copy when hardware copy is enabled. Removing copy transactions from
the server workload greatly increases the speed of these copy functions
while reducing the impact to the ESX server.
How effective is the VAAI full copy offload process?
During IBM lab testing, data retrieved from the VMware monitoring tool,
esxtop showed that commands per second on the ESX host were
reduced by a factor of 10. Copy time reduction varies depending on the
VM but is usually significant (over 50% for most profiles).
IBM Corporation 2011 16 | P a g e
17. A few examples of this performance boost at customer data centers are
shown in Table 1: Field results for VAAI full copy
.
Customer Test Before VAAI After VAAI Time
reduction (in
percentage)
Major financial 2 VMs 433 sec 180 sec 59%
Electric 2 VMs 944 sec 517 sec 45%
company
Petroleum 40 VMs 1 hour 20 min 67%
company
Table 1: Field results for VAAI full copy
Full copy effect: Thousands of commands and IOPs on the ESX server are
freed up for other tasks and promote greater scalability.
Hardware-assisted locking (atomic test and set)
Just as important as the demonstrated effect of hardware-assisted copy,
the hardware-assisted locking primitive also greatly enhances VMware
cluster scalability and disk operations for clustered file system (VMFS)
with tighter granularity and efficiency.
It is important to understand why locking occurs in the first place. For
block storage environments, VMware data stores are formatted with
VMFS. VMFS is a clustered file system that uses Small Computer System
Interface (SCSI) reservations to handle distributive lock management.
When there is a change to the metadata of the file system by an ESX
server, the SCSI reservation process ensures that shared resources do
not overlap with other connected ESX hosts by obtaining exclusive
access to the logical unit number (LUN).
A SCSI reservation is created on VMFS when (not a complete list):
• Virtual Machine Disk (VMDK) is first created
• VMDK is deleted
• VMDK is migrated
• VMDK is created via a template
• A template is created from a VMDK
• Creating or deleting VM snapshots
• VM is switched on or off
Although normal I/O operations do not require this mechanism, these
boundary conditions have become more common as features such as
vMotion with Distributed Resource Scheduler (DRS) are used more
frequently. This SCSI reservation design leads to early storage area
IBM Corporation 2011 17 | P a g e
18. network (SAN) best practices for vSphere to dictate a limit in cluster size
for block storage (about 8 to 10 ESX hosts).
With hardware-assisted locking as shown in Figure 8, LUN locking
processing is transferred to the storage system. This reduces the number
of commands required to access a lock, provides locks to be more
granular, and leads to better scalability of the virtual infrastructure.
V V V V V V
M M M M M M
D D D D D D
K K K K K K
Figure 8: VAAI Atomic test and set primitive
Hardware-assisted locking effect: Hardware-assisted locking will
increase VMs per data store, ESX servers per data store, and overall
performance. This functionality coupled with 60 processors and 360 GB
of cache memory for the XIV Storage System Gen3 helps provide better
consolidation, density, and performance capabilities for the most
demanding virtual infrastructures.
Block zeroing (write same)
Block zeroing, as shown in Figure 9, is designed to reduce the amount of
processor and storage I/O utilization required to write zeroes across an
entire EZT VMDK when it is created. With the block zeroing primitive,
zeroing operation for EZT VMDK files are offloaded to the XIV Storage
System without the host having to issue several commands.
Block Zeroing
Enabled
Zero
Zero
o
Zero
Zero
Zero
r
Ze
Zero
0 0 0 0 0 0 0 0 0 0
IBM Corporation 2011 18 | P a g e
19. Figure 9. The VAAI write same or block zeroing primitive
Block zeroing effect: Block zeroing reduces overhead and provides
better performance for creating EZT virtual disks. With XIV, EZT volumes
are available immediately through fast write caching and de-staging.
VAAI support on XIV storage systems liberates valuable compute
resources in the virtual infrastructure Offloading processor and disk
intensive activities from the ESX server to the storage system provides
significant improvements in vSphere performance, scalability and
availability.
Note: Before installing the VAAI driver for the XIV storage system, ensure
10.2.4a or higher is the installed microcode. For vSphere 5.x and later,
the VAAI driver is no longer required for IBM Storage.
4.8.2. vStorage APIs for Storage Awareness (VASA)
The IBM Storage provider for VMware VASA, illustrated in Figure 10,
provides even more real-time information about the XIV Storage System.
VMware vStorage APIs for Storage Awareness (VASA) enable vCenter to
see the capabilities of storage array LUNs and corresponding datastores.
With visibility into capabilities underlying a datastore, it is much easier to
select the appropriate disk for virtual machine placement. The IBM XIV
Storage System VASA provider for VMware vCenter adds:
• Real-time disk status
• Real-time alerts and events from the XIV Storage System
to vCenter
• Support for multiple vCenter consoles and multiple XIV
Storage Systems
• Continuous monitoring through storage monitoring service
(SMS) for vSphere
• Foundation for future functions such as SDRS and policy-
driven storage deployment.
IBM Corporation 2011 19 | P a g e
20. Figure 10. VASA block diagram
Adding VASA support, available in vSphere 5, allows VMware and Cloud
administrators insights which lead to improved availability, performance,
and management of the storage infrastructure.
In addition to VASA, the XIV Storage System also provides a vCenter Plug-
in for vSphere 4 and vSphere 5, which extends management of the storage
to provisioning, mapping, and monitoring of replication, snapshots, and
capacity.
5. Conclusion
Demonstrated through this set of IBM functional tests, VMware vSphere 5 and the
IBM XIV Storage System Gen3 storage solution seamlessly complement each other
as an efficient storage virtualization solution. Evaluation testing verified that VMware
vSphere 5 and the IBM XIV Storage System Gen3 consistently performed as
expected. The test setup and results can be further evaluated by exploring
Appendices A through G.
The release of VMware vSphere 5 is accompanied by many new and improved
features. VMware vSphere Storage Distributed Resource Scheduler (SDRS)
aggregates storage resources from several storage volumes into a single pool, and
simplifies storage management. Profile Driven Storage enables easy and accurate
selection of the correct datastore on which to deploy Virtual Machines. Storage I/O
Control provides cluster-wide I/O sharing and limits for datastores. VAAI, integrated
into vSphere 5, provides enhanced performance via storage array exploitation
without the need for a plug-in. VASA delivers realtime VMware administrator
discovery of storage: capacity, capabilities, events and alerts. With the addition of
these new features IT professionals can realize more efficient utilization of storage
resources to help achieve higher productivity at reduced costs.
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21. For more information regarding VMware vSphere 5 and the IBM XIV Storage System
Gen3, reference the following links:
VMware:
www.vmware.com/products/vsphere/overview.html
IBM XIV Storage System Gen3
ibm.com/systems/storage/disk/xiv/resources.html
Iometer
Iometer is downloaded from www.iometer.org/ and distributed under the terms of the
Intel Open Source License. The iomtr_kstat kernel module, as well as other future
independent components, is distributed under the terms of the GNU Public License).
IBM Corporation 2011 21 | P a g e
22. Appendix A (Iometer for performance testing)
1. Test objective: Performance of VMware vSphere 5.0 using XIV disk and
network controllers.
2. Setup Steps: Create 3 New Virtual Machines on vSphere
2.1. Download Windows 2008 R2 from the Microsoft website
www.microsoft.com/en-us/server-cloud/windows-server/2008-r2-trial.aspx.
2.2. Download the MS 2008 R2 ISO to vSphere machine.
2.3. On the vSphere 5.0 machine, open vSphere.
2.4. Right Click on ESX server and Select “New Virtual Machine.”
2.5. Select “Name:” Type a name for Virtual Machine; for the tested
configuration, the name used was “New Virtual Machine.”
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23. 2.6. Select “Next.”
2.7. Select VM Storage.
2.8. Select “Next.”
2.9. Select Guest Operating System “Windows” Version type.
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24. 2.10. Select “Next.”
2.11. Select Create Network Connections.
2.12. Set “How many NICs do you want to connect” to “1.”
2.13. Select NIC 1.
2.14. Select Adapter, for this test, “E1000. ”
2.15. Select “Next.”
2.16. Select “Virtual disk size:”
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25. 2.17. Select “Next.”
2.18. Select “Finish” to finish the VM creation.
2.19. Select the Virtual Machine just created.
2.20. Right Click on VM.
2.21. Select “Open Console.”
2.22. Select “Power on” (Green Arrow).
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26. 2.23. Select “CD tool.”
2.24. Select “Connect to ISO image on local disk.”
2.25. Select WS 2008 R2 ISO.
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27. 2.26. Select “Open.”
2.27. After executing windows server install, assign IP address.
2.28. Right Click on VM.
2.29. Select “Open Console.”
2.30. Run Windows updates, and Windows activation.
2.31. Shutdown Windows server.
2.32. Install test hard drives (XIV Gen3).
2.33. Right click on VM.
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28. 2.34. Select “Edit Settings”
2.35. Select “Add”
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29. 2.36. Select “Hard Disk”
2.37. Select “Next” and Select “Next”
2.38. Select “Disk Size” 40 GB
2.39. Select “Specify a datastore or datastore cluster:”
2.40. Select “Browse”
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30. 2.41. Select appropriate disk volume - In this case is “XIV-ISVX8_X9”
2.42. Select “OK”
2.43. Select “Next”
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31. 2.44. Select “Next”
2.45. Select “Finish”
2.46. Start the VM Select “Power on” (Green Arrow)
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32. 2.47. Select “VM.”
2.48. Select “Guest.”
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33. 2.49. Select “Send Crtl+Alt+del.”
2.50. Enter password
2.51. Select VM.
2.52. Select “Guest.”
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34. 2.53. Select “Install/Upgrade VMware Tools.”
2.54. To add newly created disk to Windows server, select “Start.”
2.55. Right Click “My Computer.”
2.56. Select “Manage.”
2.57. Select “Offline disk.”
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35. 2.58. Right Click, and select “Online.”
2.59. Right click on volume
Select “New Simple Volume”
Login to VM
2.60. Select “Next.”
2.61. Select “Assign Drive” and select “Next.”
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36. 2.62. Select “Volume label,” in this case disk 3, and select “Next.”
2.63. Select “Finish.”
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37. 2.64. Finished
2.65 Please repeat the above procedure a total of three times to create
disk 1, disk 2 and disk 3.
2.66 Now perform a remote desktop (RDP) to the VM:
2.67. Download Iometer from this website:
http://www.Iometer.org/doc/downloads.html
2.68. Download Version 2006.07.27 (or latest version).
[download] Windows i386 Installer and prebuild binaries cc5814fd01a0ef936964d590e4bbce7a
2.69. Download Iometer to the desktop.
2.70. Double click on Iometer-2006.07.27.win32.i386-setup.
2.71. Select “Run.”
2.72. Select “Next.”
2.73. Read License Agreement.
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38. 2.74. Select “I Agree” and select “Next” to choose the components to install.
2.75. Select “Install.”
2.76. Select “Finish” to finish installing Iometer.
3. Test Steps to create 3VMs and test performance via Iometer
3.1. To Run Iometer, select windows “Start.”
3.2. Select “All Programs.”
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39. 3.3. Select “Iometer 2006.07.27” or the latest version available.
3.4. Select “Iometer”
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40. 3.5. Select “+” under “All Managers”
3.6 Create a Worker; select “Worker 1.”
3.7. Select desired drive to use, in this case, E: disk 1.
3.8 Add Network Targets; select to add Network Targets.
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41. 3.9. Select “Worker 2.”
3.10. Select Network from the Network targets tab.
3.11. Select “Access Specifications.”
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42. 3.12. Select “New.”
3.13. Select “Name.”
3.14. Create test name.
3.15. Select “Transfer Request Size” and set to “2 KB.”
3.16. Change to 8KB to mimic SQL server.
3.17. Select “Percent Read/Write Distribution.”
3.18. Change specification to 30% Write and 70% Read.
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43. 3.19. After Changes, Select “OK.”
3.20. Scroll down to find test name.
3.21. Select test name.
3.22. Select “Add.”
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44. 3.23. Select “Test Setup.”
3.24. Select “Test Description.”
3.25. Type test name.
3.26. Select “Run Time.”
3.27. Set to 1 hour.
3.28. Select “Results Display.”
3.29. Select “Update Frequency (seconds).”
3.30. Set Update Frequency to 1 second to view results.
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45. 3.31. Select Start (Green Flag).
3.32. Select “File name.”
3.33. Select “Save.”
The test will run for 1 hour.
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46. 3.34. Start Results.
4. Iometer performance results
(3) VM, (1) CPU, 4GB Memory, (3) 40GB XIV LUNS were used for this
test.
The results screen shows the achieved IOPS, throughput and CPU
utilization for VM1; the tests were repeated for VM2 and VM3. These
tests showed the possible throughput of 3 VMs and the IBM XIV Gen3
storage array configuration without any special tuning. The 3 VMs
averaged approximately 75,000 IOPS with <0.5ms latency.
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47. Appendix B (vSphere vMotion)
1. Test object: vSphere vMotion - Transfer time of VMs to local disk (Vmware
5.0)
2. Setup steps: This section demonstrates vMotion using local disk
2.1. Download a stop watch from http://download.cnet.com/Stop-
Watch/3000-2350_4-10773544.html?tag=mncol;5 and install
Screen Setup for test:
3. Test Steps: Test transfer time to migrate data to local disk
3.1. Select Virtual Machine (VM).
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48. 3.2. Right click on VM.
3.3. Select “Migrate.”
3.4. Select “Change datastore” and select “Next.”
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49. 3.5. Select a Local Datastore “ISVX8-local-0” and select “Next.”
Start of test
3.6. Start the Stopwatch; Select “Restart.”
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50. 3.7. At the Completion of the test, select “Pause.”
End of the test
4. Results:
The recorded transfer time migrating VMs to local disk (Vmware 5.0) was
10 min 3 seconds.
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51. Appendix C (Transfer times of VMs to XIV LUNs (SAN))
5. Test object: Transfer times of VMs to XIV LUNs (SAN)
6. Setup steps: This section demonstrates vMotion using XIV
2.1. Download a stop watch from http://download.cnet.com/Stop-
Watch/3000-2350_4-10773544.html?tag=mncol;5 and install.
Screen Setup for test
7. Test Setup: Test transfer time to migrate data to XIV disk.
3.1. Select Virtual Machine (VM).
3.2. Right click on VM.
3.3. Select “Migrate.”
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52. 3.4. Select “Change datastore” and select “Next.”
3.5. Select the XIV LUN ”XIV_ISVX8_X9” and select “Next.”
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53. Start of test
3.6. Start the Stopwatch
3.7. Select “Finish”
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54. 3.8. At the Completion of the test, select “Pause” and record the total
migration time.
End of test
8. Results:
The recorded transfer time migrating VMs to XIV Gen3 (Vmware 5.0) was
1 min 31 seconds.
For the two tested VMs, transferring all data from the server to XIV was
6.7 times faster than from the server to the local disk for the tested
configuration, demonstrating the efficiency and synergy using XIV and
vSphere vMotion.
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55. Appendix D ( vSphere High Availability)
9. Test object: vSphere High Availability - Failover of an ESX server
10. Test steps: Create a VMware vSphere 5.0 with a cluster environment
2.1. In the VMware cluster environment, select a VM that is not Fault
Tolerant.
2.2. Right Click on the VM.
2.3. Select “Edit Settings.”
2.4. Ensure that the VM uses XIV Gen3 hard disk as in the example
below; select “OK.”
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56. 2.5. Right click on VM.
2.6. Select “Fault Tolerance.”
2.7. Select “Turn On Fault Tolerance.”
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57. 2.8. Select “Yes”
2.9. Results
Fault Tolerance is now active.
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58. 2.10. Right click on VM.
2.11. Select “Power” and “Power On.”
2.12. Set up complete.
11. Test Steps:
3.1. Right Click on VM.
3.2. Select “Fault Tolerance.”
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59. 3.3. Make note of the “Host and Storage.“
3.4. Select “Test Failover.”
Observe that “VM and Storage” has moved to a new host.
12. Results:
The VM moved to a new ESXI host and the storage seamlessly moved
with it.
Appendix E (vSphere Storage DRS)
1. Test object: vSphere Storage DRS
2. Setup steps: Demonstrate SDRS using VMware vSphere 5.0 startup
screen
2.1. Select “Inventory.”
2.2. Select “Datastore and Datastore Cluster.”
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60. 2.3. Right click on “Datacenter.”
2.3. Select “New Datastore Cluster.”
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61. 2.4. Create the Datastore Cluster Name.
2.5. Select “Turn on Storage DRS,” and select “Next.”
2.6. Select “Fully Automated” and select “Next.”
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62. 2.7. Select “Show Advance Options.”
2.8. Review Settings (Use Defaults), and select “Next.”
2.9. Select “Cluster,” and select “Next.”
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63. 2.10. Select the datastore to use, then select “Next.”
2.11. Review results under “Ready to Complete.”
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64. 2.12. Select “Finish.”
The new cluster datastore shows all operations were completed
successfully.
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65. 2.13. Build a new virtual machine.
2.14. Right Click on “Cluster.”
2.15. Select “New Virtual Machine,” then select “Next.”
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66. 2.16. Name the virtual machine and select “Next.”
2.17. Select host and then select “Next.”
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67. 2.18. Select datastore cluster, then select “Next.”
2.19. Select Guest Operating System, and select “Next.”
2.20. Select “Create Network Connections,” and select “Next.”
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68. 2.21. Specify the virtual disk size, and select “Next.”
2.22. Select “Show all storage recommendations.”
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69. 2.23. Select “Continue.”
2.24. Select “Apply Recommendations.”
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70. 2.25. Observe that “Apply Storage DRS recommendations” has
completed.
Exploring the Datastore Cluster
2.26. Select “Datastore and Datastore Cluster” from vSphere Home
Screen.
2.27. Select datastore.
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71. 2.28. Right click.
2.29. Right click on new VM created.
2.30. Select “Migrate.”
2.31. Select “Change datastore,” and select “Next.”
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73. SDRS set up completed.
3. Test Steps:
3.1. Select Datastore cluster.
3.2. Select “Run Storage DRS.”
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74. “Relocate virtual machine” shows test status of “Completed.”
4. Results: Storage DRS (SDRS)
When an imbalance occurs on the datastore, Storage DRS recommends a
virtual machine to be migrated. Storage DRS will make multiple
recommendations to solve datastore imbalances.
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75. Appendix F (Profile-Driven Storage)
1. Test object: Profile-Driven Storage
2. Setup steps: This test demonstrates Profile-Driven Storage
2.1. Select “VM Storage Profile” from the Home vSphere window.
2.2. Select “Enable VM Storage Profiles.”
2.3. Select “Enable.”
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76. 2.4. Note that VM Storage Profile Status is enabled and select “Close.”
2.5. Select “Manage Storage Capabilities.”
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77. 2.6. Select “Add.”
2.7. Select “Name,” type “Gold.”
2.8. Select “Description,” type “Gold Storage Capability.”
2.9. Select “Ok” and “Close.”
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78. 2.10. Note: Recent Tasks and select “Home.”
2.11. Select “Datastores and Datastores Cluster” from the Home vSphere
window.
2.12. Select disk choice for User-Defined Storage Capability:
2.13. Select disk and right click.
2.14. Select “Assign User-Defined Storage Capability.”
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79. 2.15. Select “Name” pull down, select “Gold,” and select “Ok.”
2.16. Select “Summary.”
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80. 2.17. Select “Home.”
2.18. Select “VM Storage Profiles” from the vSphere Home screen.
2.19. Select “Create VM Storage Profile.”
2.20. Select “Name” type: Gold Profile.
2.21. Select “Description” type: Storage Profile for VMs that should reside
on Gold storage, and select “Next.”
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82. 2.23. Select “Finish.”
2.24. Select “Gold Profile.”
2.25. Select “Summary.”
2.26. Observe the settings for later comparison.
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83. 3. Test Steps:
3.1. Assign a VM storage profile to a VM.
3.2. Select “Home.”
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84. 3.3. Select “Hosts and Clusters.”
3.4. Select a VM.
3.5. Right click the VM.
3.6. Select “VM Storage Profile.”
3.7. Select “Manage Profiles.”
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85. 3.8. Select “Home VM Storage Profile.”
3.9. Select “Gold Profile” from pull down menu.
3.10. Select “Propagate to disks,” and select “Ok.”
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86. 3.11. Observe the setting in “VM Storage Profiles for virtual disks” for
future use and select “Ok.”
3.12. Observe in VM Storage Profiles section the profile is
“Noncompliant,” as the storage characteristics in the “to” storage do not
meet the same requirements.
3.13. Right click on VM.
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87. 3.14. Select “Migrate.”
3.15. Select “Change datastore,” and select “Next.”
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88. 3.16. Select “VM Storage Profile.”
3.17. Select “Gold Profile.”
3.18. Select Compatible disk, and select “Next.”
Note: the VM is being migrated.
3.19. Select “Refresh.”
4. Results: Profile Driven Storage
Note the VM Storage Profile is now Compliant.
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89. Gold VM Storage Profile:
This test demonstrates that with Profile Driven Storage, a user is able to
ensure physical storage characteristics are consistent between VM
migrations.
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90. Appendix G (Storage I/O Control)
1. Test object: Storage I/O Control
2. Setup steps: Create a VM with 2 hard drives to demonstrate Storage I/O
Control
2.1. Start VM.
2.2. Use remote desktop (RDP) to go to the VM.
2.3. Install Iometer from http://www.Iometer.org/doc/downloads.html
2.4. Once installed, run Iometer.
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91. 2.5. Select “Worker 1.”
2.6. Select “E: disk1.”
2.7. Select “Access Specifications,” and select “New.”
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92. 2.8. Set “Transfer Request” Size to “10 Megabytes, 2 Kilobytes, 0 Bytes.”
2.9. Set “Percent Read/Write Distribution” to 75% Write / 25% Read and
select “Ok” (these settings provide a heavier load on the VM).
2.10. Select “Untitled 1” under Global Access Specifications.
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93. 2.11. Select “Results Display.”
2.12. Select “Update Frequency” to “1.”
2.13. Select “Green flag” to start.
2.14. Select “Save” to save results.
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94. 2.15. Return to vSphere.
2.16. Select “Home.”
2.17. Select “Datastores and Datastore Clusters.”
2.18. Select the Host running the VM.
Note Storage I/O Control is “Disabled”
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95. 2.19. Select “Properties.”
2.20. Set “Storage I/O Control” to “Enabled.”
2.21. Select “Advanced.”
2.22. Select “OK.”
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96. 2.23. Select “OK.”
2.24. Select “Close.”
2.25. Go to the VM used for testing and “Edit Settings.”
2.26. Select “Resources.”
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97. 2.27. Select “Disk,” and select “OK.”
Note: Storage I/O Control (SIOC) is set on Disk 2.
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98. 2.28. Set Hard disk 2 “Share” to High and “Limit – IOPS” to 100.
3. Test Steps: Demonstrate Storage I/O Control
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99. 3.1. Now look at SIOC’s enforcing of the IOPS limit. Go back to the
vSphere Client Performance tab or the virtual machine’s Iometer results
to see the number of IOPS currently being generated. The value for this
exercise is approximately 500–600 IOPS.
3.2. Go to the VM running Iometer.
3.3. Stop Iometer.
3.4. Change “# of Outstanding I/Os” to 65.
3.5. Restart Iometer.
3.6. Go to Results Display.
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100. 4. Results: Storage I/O Control
Implementing Storage I/O Control recommendations shows a gradual
movement towards the prioritizing of shares. The test demonstrates a
gradual increase in the IOPS for the virtual machine with 2000 shares and
a gradual decrease in IOPS for the virtual machine with 1000 shares. This
completes the evaluation of Storage I/O Control.
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102. Performance is based on measurements and projections using standard IBM
benchmarks in a controlled environment. The actual throughput or performance that any
user will experience will vary depending upon considerations such as the amount of
multiprogramming in the user's job stream, the I/O configuration, the storage
configuration, and the workload processed. Therefore, no assurance can be given that
an individual user will achieve throughput or performance improvements equivalent to
the ratios stated here.
Photographs shown are of engineering prototypes. Changes may be incorporated in
production models.
Any references in this information to non-IBM websites are provided for convenience
only and do not in any manner serve as an endorsement of those websites. The
materials at those websites are not part of the materials for this IBM product and use of
those websites is at your own risk.
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