How would I use Application Workload Modeler in my environment?
You can use Application Workload Modeler to assist in performance and capacity planning for your network and networked applications. In general, it can be used to plan for:
- The deployment of a new application that generates network traffic
- Increased use of an existing application that generates network traffic
- A change in your network infrastructure
- A change in hardware or software that may impact the performance of your network
Following are some specific examples:
- Enhanced Network Connectivity to S/390 and zSeries Hardware: This will likely include deployment of an OSA Express adapter in place of existing connectivity such as an OSA/2 adapter or ESCON Channel attached routers. AWM can be used to model network traffic through both new and old connectivity options and measure the performance characteristics that each solution offers. This information can be helpful in justifying the change from both a cost and performance benefit perspective.
- General Changes in the Network Infrastructure: You may be considering a variety of changes, including routers, physical networks (for example, Token ring to Gigabit Ethernet), or the number of networks connected to your OS/390 or z/OS systems. AWM can help you measure the performance impact these changes may have on end user response times when accessing applications on S/390 and zSeries.
- Converging to an IP WAN Backbone Using Enterprise Extender: With IP networks becoming prevalent over the last few years, many OS/390 and z/OS customers have been exploring options that allow them to converge to an IP wide area network (WAN) backbone for both SNA and TCP/IP traffic. Enterprise Extender (EE) is the solution many of these customers are turning to as it allows you to achieve these objectives without any changes to the large number of SNA applications you have invested in over the years.
- TN3270 Server Placement: When choosing between an outboard TN3270 server or a TN3270 server on your z/OS or OS/390 system, AWM can be used to model and analyze the performance characteristics and resource requirements of these solutions by generating the desired workload level of TN3270 clients and providing detailed performance measurements. AWM can help in this evaluation, by answering questions, such as the following:
- What is the maximum number of clients that an outboard TN3270 server can support?
- How many outboard TN3270 servers can a z/OS or OS/390 TN3270 server replace?
- What are the MIPS requirements for a z/OS or OS/390 TN3270 server?
- Which TN3270 server solution provides the best response time to end users?
- What would be the impact of adding another 20,000 TN3270 clients?
- What is the performance/resource impact of using SSL with TN3270?
- Deploying SSL for TCP/IP Workloads: AWM can be especially valuable in modeling and measuring the performance impact of deploying an SSL solution on OS/390 or z/OS. AWM's SSL support not only allows users to evaluate the network impact of SSL, but also to measure the impact of using SSL on the OS/390 or z/OS host by actually driving the operating system's SSL layer for the encryption and decryption of the network traffic being generated. This allows users to not only understand the impact of SSL on the network and application response time, but also the impact on host MIPS.
- Deploying VPNs for TCP/IP Workloads: Another common technology that is deployed to enhance TCP/IP security is IPSec, which allows you to define Virtual Private Networks (VPNs). A common question that arises with the deployment of VPNs is the impact that this enhanced level of security has on performance. AWM can be used in this scenario to model network and network application performance with and without VPNs so that you can perform better network provisioning (for example, number of routers, number of VPNs required, etc.)
- Deployment of Load Balancing Solutions: AWM can help you understand the performance characteristics and resource requirements of a connection load balancing solution, such as the Sysplex Distributor function provided by the Communications Server for z/OS and OS/390. To do this, use AWM to generate a predictable TCP/IP workload with and without load balancing deployed and compare the results in the detailed performance measurements provided by AWM.
- Server Consolidation on zSeries: Customers considering consolidating existing workloads on zSeries processors can use AWM to assess the network performance impact of doing so. For example, if you move your Tier 2 application server workloads from several distributed Unix platforms to Linux for zSeries LPARs, these application servers can use the HiperSockets network to access your business data that resides on a z/OS LPAR in the same zSeries processor. (HiperSockets is the internal, high speed, low latency network that is available on zSeries processors.) AWM can be used in this scenario to compare the network communications over the traditional distributed network and the HiperSockets network.
- Exploitation of Network Quality of Service (QoS): AWM is a very useful tool in modeling and measuring the effect of QoS on TCP/IP network traffic. Note that QoS deployment does not necessarily imply global deployment within a customer's network. A customer may have to manage multiple types of QoS policies across the variety of vendor networking equipment that they deploy. A z/OS and OS/390 customer may be initially only interested in some of the host capabilities in this area, such as outbound traffic priority queuing available with the Communications Server and OSA Express Adapters in QDIO mode. Using AWM, you can generate repeatable customized network traffic loads using various QoS policies to determine which is most effective in your environment.
- Deployment of IPv6 Networks: As the technology of the next generation Internet Protocol (IPv6) matures, you may be planning to deploy IPv6 networks. AWM can be very useful in testing and measuring the performance of IPv6 network infrastructures before any IPv6 applications are developed and deployed. Also, given that most IPv6 networks will likely share the same physical network infrastructure as IPv4 networks, AWM can be used to model the impact that IPv6 traffic may have on existing IPv4 network traffic.
- New or Changed TCP/IP or SNA Applications: AWM can be used to model the network traffic for TCP/IP and SNA applications prior to the development of new applications or prior to implementing changes to existing applications. AWM allows a variety of application network traffic to be modeled, such as interactive workloads, connection intensive workloads, or bulk data transfer workloads. This AWM feature is very useful in determining the network performance characteristics of the new or changed application and in determining whether the existing network infrastructure can sufficiently handle any additional network traffic or whether the infrastructure requires some upgrades to meet performance objectives.
- Hardware and Software Changes to Your System or Network: AWM can be used to benchmark existing workloads on your network. When any hardware or software change is then made to your system or network, these benchmarks can be run again to measure the impact of the change on these workloads. Again, this can be done while the change is still in test, before it goes into production.
- Determining the Resource and Performance Characteristics of Well Known TCP/IP Servers: AWM can be used to simulate and generate a variety of TCP/IP client application workloads targeted to standard, well known TCP/IP server applications. This allows you to simulate large client workloads against these server applications while obtaining detailed performance and resource statistics. With this information you can better determine the ideal location/platform for the server application and the resource requirements for the workload. Client application workloads that can be modeled include:
- CICS socket applications
- Dynamic Host Configuration Protocol (DHCP)
- Domain Name System (DNS)
- File Transfer protocol (FTP)
- SAP Integrated Call Level Interface (ICLI)
- Simple Mail Transfer Protocol (SMTP)
- TN3270, TN3270E
- Express Logon
- Web Servers (HTTP, HTTPS).