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Dell Hardware Sizing Guide Introduction Today’s educational institutions increasingly depend on enterprise course management software systems to service the needs of their students, faculty, and administrators. It is important to deliver a high quality of service to this community of users through optimizing an e-Learning platform for maximum performance and availability. This sizing guide is designed to help clients of Blackboard achieve high service levels and reduce risk by properly configuring and sizing the implementation of Blackboard Learn™ software on Dell application and database servers. Blackboard Learn™ provides the critical enabling technologies to help institutions evolve into Blackboard’s vision for the 21st Century Learning Institution, which is unconstrained by time and place, and can operate simultaneously in a local and global context. Blackboard’s enterprise course management solutions have been proven at thousands of educational institutions worldwide. As institutions have continued to embrace the need for course management and other enabling technologies for 21st century learning, Blackboard solutions have become a critical part of the IT infrastructure that enables success in today’s global marketplace. Blackboard Learn includes Blackboard’s course management system, Course Delivery as well as other core applications. Additional modules include Community Engagement, Content Management, and Outcomes Assessment.

Recommended Configurations The recommended configuration pictured in Figure 1 is based on a scalable entry-level configuration for the Blackboard Reference Architecture on Dell hardware. The information in this section is based on joint performance testing and benchmarking between Blackboard and Dell in order to achieve maximum performance throughput for each configuration.

Figure 1 Blackboard Reference Architecture on Dell Hardware Blackboard Inc © 2008

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Blackboard Performance Lab

Dell Hardware Sizing Guide

Methodology Sizing is a three-step process consisting of two modeling exercises and performance testing. The modeling exercises are used to gather statistical evidence regarding how users interact with the system. The data generated from these exercises is subsequently used in a series of performance tests. Performance tests help quantify what the system will look like under hypothesized workloads and scenarios. The process begins with understanding how Blackboard clients have used the product in the past. This form of sampling is called behavior modeling. The objective of this form of sampling is to gather meaningful data representing the following: • Who is using the system? • What is being done? • Where are they performing their operations? • When are they performing their operations? • How long are users spending performing their operations? Predictive modeling is used for new performance testing new features. Little information can be collected about a feature that has never been built. Because of this, we hypothesize the expected behavior of users interaction with these new features. The data collected from both modeling exercises is then used for performance testing and benchmarking. Performance benchmarking is conducted by Blackboard with a selected partner of choice such as Sun Microsystems, Dell, Microsoft, or Oracle at the Blackboard Performance Laboratory using a combination of purchased and donated equipment from a partner. Performance testing and benchmark activities focus primarily on the performance (response times exhibited by users) and scalability of the system (utilization of system resources such as CPU, memory, and I/O). HP/Mercury LoadRunner is the simulation tool of choice for generating workload.

Sizing Blackboard Learn Sizing the Application The Dell server platform architecture is capable of supporting Linux and Windows deployments on Intel and AMD processor lines. Rack mount and highly dense blade servers are both available. Blackboard Learn has been benchmarked on a variety of Dell dual and quad core systems. Most often these systems contain two or four sockets and 8GB to 16GB of memory. Throughput performance increases depending on which CPU model is chosen. At the time of this publishing, the Quad Core Intel® Xeon® 5440 2.83GHz processor offers the best overall price performance. The Quad Core Intel® Xeon® 5460, 4MB Cache, 3.16GHz processor offers the best throughput performance. To achieve maximum throughput, each Dell PowerEdge server should run multiple clustered Java Virtual Machines (JVM) of Blackboard Learn to take advantage of all cores available on this configuration. This can be achieved through clustering the product, or through virtualization techniques. Performance benchmarking has shown that this server can reach adequate CPU saturation when running four clustered instances of Blackboard Learn before user response time degrades. The balancing of workload across multiple Java Virtual Machines is preferred. Dual core systems can also be deployed, but given the cost considerations quad core systems are providing the best overall cost performance value. The Dell PowerEdge servers scale horizontally in a load-balanced configuration and vertically in a clustered JVM configuration. Clustering is a deployment feature introduced in Release 7, Application Pack 2 and available in all subsequent releases. The memory requirements of the server vary depending on the number of clustered instances running. Typically, each JVM is configured for roughly 1.5GB of memory. An additional 1GB is required for the Apache or IIS web server. The remaining 1GB is available for the operating system and trivial applications running on the system such as monitoring agents.

Blackboard Inc © 2008

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Blackboard Performance Lab

Dell Hardware Sizing Guide

Virtualization at the Application Layer Blackboard has executed over 800 hours of regression testing and benchmarking of Blackboard Learn using virtualization technologies such as VMware ESX. Overall performance and throughput can be vastly improved through the use of virtualization. Our performance benchmarks have demonstrated 20 percent to 40 percent additional throughput and lowered response times by breaking up a bare metal server into multiple virtualized instances. The application best performs with smaller workloads assigned to virtual instances with one to two virtual CPUs available. Using a dual-socket quad-core system (8-cores), a deployment of four to eight virtual instances can successfully be deployed. Additional memory would be required for the overall server requirements. We recommend 2 to 4 GB of RAM per virtual instance.

Dell Configuration Information Description

Small Institution Configuration

Medium Institution Configuration

Large Institution Configuration

User Community Size

1,000 to 10,000

10,000 to 25,000

25,000 to 50,000

• 500 to 1,000 active courses

Sizing Assumptions

• Up to 1,200 active users with 2 application servers • Assumes application layer clustering and hardware load-balancing

Application Tier

Cluster Capacity

Virtualization Capacity

• 1 to 2 Dell PowerEdge 1950 or 1955 Blade Servers • 2 x Dual Core Intel® Xeon® •

8GB memory

Calibrated to 2 Java Virtual Machines per dual core Server

Calibrated for 1 virtual instance per 1 to 2 logical cores

• 1,000 to 5,000 active courses

• 5,000 to 25,000 active courses

• Up to 2,400 active users with 4 application servers

• Up to 3,600 active users with 8 application servers

• Assumes application layer clustering and hardware load-balancing

• Assumes application layer clustering and hardware load-balancing

Candidate for Oracle RAC

Candidate for Oracle RAC

• 4 to 6 Dell PowerEdge 1950 or 1955 Blade Servers

• 2 x Dual or Quad Core Intel® Xeon®

6 to 10 Dell PowerEdge 1950 or 1955 Blade Servers

• 2 x Dual or Quad Core Intel® Xeon® •

8 to 16GB memory

Calibrated to 2 Java Virtual Machines per dual core Server

Calibrated to 2 Java Virtual Machines per dual core Server

Calibrated to 4 Java Virtual Machines per quad core Server

Calibrated to 4 Java Virtual Machines per quad core Server

Calibrated for 1 virtual instance per 1 to 2 logical cores

Calibrated for 1 virtual instance per 1 to 2 logical cores

8 to 16GB memory

Sizing the Database The PowerEdge 2950 III is ideal for running both Microsoft SQL Server 2005 and Oracle 10G for small and medium size institutions. Using a quad core configuration is recommended. We recommend 16GB to 32GB of memory per system. Each of these systems can be used for availability purposes in an Oracle RAC configuration or Microsoft SQL Server Active/Passive Failover Cluster. Contact the Blackboard Professional Services organization for more information about deploying Blackboard on Oracle RAC or SQL Server Failover capabilities. For large campus configurations, Dell PowerEdge R900 servers are used in lieu of the PowerEdge 2950 III server to provide increased capacity. A high availability option is supported through an optional cluster configuration with a redundant instance of the database running on a second server using Oracle RAC or SQL Server Failover capabilities to provide the redundant database functionality. The PowerEdge 2950 III with dual sockets and quad core has been calibrated to handle about two to three Dell PowerEdge 1950 III, M600 Blade Servers or PowerEdge R805 application servers. Each of these systems would also be calibrated for two to four Java Virtual Machines. The ratio of application servers changes slightly to 1 to 2 when virtualized deployments occur.

Blackboard Inc © 2008

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Blackboard Performance Lab

Dell Hardware Sizing Guide

The R900 models will support about four to seven Dell PowerEdge 1950 III, M600 Blade Servers or PowerEdge R805 application servers. Each of these systems would also be calibrated for two to four Java Virtual Machines. The ratio of application servers to database server changes slightly to three to five when virtualized deployments occur.

Sizing Storage Media and Content Storage Blackboard Learn makes use of a non-relational file system for the storage of multi-media and binary files such as text files, images, word processing documents, spreadsheets, and other file types used in teaching and learning. Blackboard recommends clients make use of a network file share (NFS) on Unix platforms or a common internet file system (CIFS) on Windows. Both of these network-based file system protocols allow for simplified management, ease of data expansion and multiple access points from applications servers. Load balanced installations can quickly make use of both file system types. Deploying storage on a local application server can also be implemented, but is not recommended. File system content can range from two to five times database content. File system content from a block perspective is touched less frequently then the database file system. Clients can opt to configure their systems to a lesser performing RAID configuration with slower spindles as I/O performance is less of a concern. The exception would be streaming content and media. Typically, we recommend that clients determine a storage quota per student and faculty member as well as account for passive users that require less storage quota. Assume that faculty will have greater storage requirements. Below is a simple example:

Profile

Quota

Users

Storage Needs

Faculty

5GB

500

2.5 TB

Student

500MB

10,000

5TB

Observer

20MB

1,000

20GB

Sizing the file system is dependent on archival strategies, data management policies, RAID configuration, and I/O performance standards. We typically assume that the file system will require about 100 I/O per second per application server at peak. To calculate your I/O per second need, multiply this metric against the number of application servers in your deployment.

Database Data File Storage Blackboard Learn makes use of a relational database system (Oracle and SQL Server) for the storage of database content. Clients may make use of a network file share (NFS), ISCSI (networked block-level) or direct attached storage (block-level) on Unix platforms. Windows SQL Server clients may only use ISCSI (networked block-level) or direct attached storage (blocklevel). The database storage requirements of institutions can vary. Typically, database content can range from two to five times less then file system content. Sizing the database is dependent on archival strategies, data management policies, RAID configuration, and, most importantly, I/O performance standards. We typically assume that the file system will require about 500 I/O per second per application server at peak. To calculate your I/O per second need, multiply this metric against the number of application servers in your deployment. The primary driver for database storage should be performance.

Blackboard Inc Š 2008

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Blackboard Performance Lab

Dell Hardware Sizing Guide

Small Institution Configuration

Description

• 1 Dell PowerEdge 2950 III Server

Database Tier

• 2 x Quad Core Intel® Xeon® E5440, 2x6MB Cache, 2.83GHz, 1333MHz FSB •

8 to 32GB memory

Medium Institution Configuration • 1 Dell PowerEdge R900 Server • 4 x Dual Core Intel® Xeon® E7340 Xeon, 2.4 GHz, 8M Chache, 80W, 1066MHz FSB • 16GB to 32GB memory

Large Institution Configuration • 1 Dell PowerEdge R900 Server • 4 x Quad Core Intel® Xeon X7350 Xeon, 2.93 GHz, 8M Chache, 130W, 1066 MHz FSB • 32GB memory

Storage Performance The database tier requires very high I/O performance and thus utilizes fibre channel drives with 10,000 to 15,000 RPMs. In order to deliver adequate I/O throughput, it also should make use of smaller capacity drives so that there will be more spindles to reduce seek times and improve data transfer rates. The configurations defined in this guide have been validated to support adequate I/O throughput for the user loads defined for each configuration. When sizing storage, please be sure to first determine how much storage your institution will need. Second, determine how this storage can be spread across multiple trays and disks to optimize performance throughput. Remember that the shared file system can require upwards of five times the storage of the database, however the database can utilize five times the number of I/O operations per second then the file system.

Small Institution Configuration

Description •

Content Storage Tier

Database Storage Tier

Blackboard Inc © 2008

Network Attached Storage Architecture for Linux or CIFS Architecture for Windows

Medium Institution Configuration •

Network Attached Storage Architecture for Linux or CIFS Architecture for Windows

Large Institution Configuration •

Network Attached Storage Architecture for Linux or CIFS Architecture for Windows

• Up to 2.2 TB of usable storage

• Up to 5 TB of usable storage

• Up to 10 TB of usable storage

• 7.2k to 10k RPM SATA or SAS disks

• 7.2k to 10k RPM SATA or SAS disks

• 7.2k to 10k RPM SATA or SAS disks

Network Attached Storage Architecture for Linux, ISCSI or FC-SAN

Network Attached Storage Architecture for Linux, ISCSI or FC-SAN

• Up to 300 GB of usable storage

• Up to 600 GB of usable storage

• 10k to 15k RPM FC

• 10k to 15k RPM FC

Network Attached Storage Architecture for Linux, ISCSI or FC-SAN

• Up to 1 TB of usable storage • 10k to 15k RPM FC

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Blackboard Performance Lab

Dell Hardware Sizing Guide

Conclusion The information in this sizing guide is based on analysis and benchmarking models from the Blackboard Performance Team. It is intended to provide guidance. It is not intended as a service level agreement. Deployments will differ from institution to institution based on a variety of factors including the usage of the application. Contact Blackboard Technical Solutions Engineering for more information on systems architecture design and detailed sizing questions.

www.blackboard.com Worldwide Headquarters 650 Massachusetts Avenue NW Sixth Floor Washington D.C. 20001-3796 1-800-424-9299 + 1-202-463-4860

Blackboard, the Blackboard logo, Blackboard Perfomance Lab, Blackboard Learn, Blackboard Academic Suite, Blackboard Learning System, Blackboard Community System, Blackboard Content System, Blackboard Outcomes System, and Blackboard Portfolio System are either registered trademarks or trademarks of Blackboard Inc. in the United States and/or other countries. Dell and PowerEdge are registerd trademarkes of Dell Inc. Intel and Xeon are registered trademarks of Intel Corporation. Microsoft, Windows, and SQL Server are registered trademarks of Microsoft Corporation in the United States and/or other countries. Java is a registered trademark of Sun Microsystems, Inc. in the United States and/or other countries. Oracle is a registered trademark of Oracle Corporation in the United States and/or other countries. Red Hat is a registered trademark of Red Hat, Inc. in the United States and/or other countries. Linux is a registered trademark of Linus Torvalds in the United States and/ or other countries. Apache is a trademark of The Apache Software Foundation in the United States and/or other countries. Quest, Quest Toad, Quest Spotlight, and Quest LiteSpeed are either registered trademarks or trademarks of Quest Software in the United States and/or other countries. Coradiant and Coradiant TrueSight are registered trademarks of Coradiant, Inc. Other product and company names mentioned herein may be the trademarks of their respective owners. Patents pending.

Blackboard Inc Š 2008

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