Dynameasure Enterprise 1.5

Demand for increased capacity, speed, and resources plagues every systems administrator. Network response time can slow to a crawl just because you add a few workstations to your network. Unexpected side effects (e.g., slow response times, incompatibility with existing software, a system crash) can pop up after you introduce a new software product. When you deploy new hardware, you face issues such as whether the hardware will perform as advertised and whether everything in your network will work properly once you deploy it.

Dynameasure Enterprise 1.5 by Bluecurve replaces guesswork with hard data so that you can deploy new hardware and software applications with confidence. Bluecurve's software measures end-to-end system performance from the application layer by applying controlled stress to the system. Systems administrators can use this flexible tool for server benchmarking, capacity planning, stress testing, and network analysis. Bluecurve geared Dynameasure 1.0 (see John Enck, "Dynameasure by Bluecurve: Born to Measure," November 1996) toward performance testing a Microsoft SQL Server environment using client/server hardware and software components. Bluecurve's Dynameasure 1.5 product line includes Dynameasure for SQL, Dynameasure for File Services, and Dynameasure Enterprise.

Dynameasure for SQL applies stress to the network via simulated OnLine Transaction Processing (OLTP) and SQL decision support workloads. This test service is an updated version of the SQL test service that Bluecurve provided in version 1.0. Dynameasure for File Services, new in version 1.5, measures Windows NT file services performance. This test service lets you apply copy workloads, which simulate copying files to and from a server; backup and retrieval workloads, which simulate backing up a client machine to a server and retrieving files from a server; and network application workloads, which simulate loading apps onto a client machine from a server and uploading and downloading files. Dynameasure Enterprise provides both test services, but because the Lab reviewed the SQL component in Dynameasure 1.0, I'll primarily report on the new File Services component in this review.

Dynameasure for File Services lets you create what-if scenarios of real-world network file operations. From more than 50 predefined file operations that clients typically perform, you choose one or more operations and create a simulated workload to meet your test objectives. (You can even model new users to gauge how they will affect network performance.) Each file operation uses one or more data, text, image, or binary file to perform tasks such as copying images to the server, backing up a client machine, and loading a client program. Dynameasure uses your existing network client configuration to run motors that generate client load. The motors coexist with resident client applications, so you can test your everyday operating environment while end users keep working.

Putting controlled stress on the network and assessing performance let you pinpoint server, network, and client bottlenecks. You can (and should) customize the workloads to construct scenarios that provide meaningful information specific to your network. Tailoring the file operations and analyzing the results can help you decide whether you need more CPUs, memory, disk space, or network bandwidth.

Dynameasure Preliminaries
To run Dynameasure tests, you must conFigure four components: a control client, a control server, at least one test client, and at least one test server. The control client, running either Windows NT or 95, executes an agent program known as the Manager. The Manager is the interface through which you set up, run, monitor, and analyze the tests. The control server hosts databases that contain the test data and store the test results. Test clients obtain the test parameters from and record their results to the control server. For most tests, you will use several test client systems. Each test client, running Win95 or NT, executes an operator program. Each operator can start 25 motors (or 100 motors with an additional licensing agreement); each motor generates the workload of one user. The final component, the test server, is the focal point of the test: On the test server, you load the test data set, the data that the test clients access during the test run.

Bluecurve (and the Windows NT Magazine Lab) recommends that you use separate computers for the control server and the test server. Dynameasure stores the transaction results from the tests in a database on the control server. With separate machines, the I/O load of updating the transaction results database does not influence the I/O load on the test data set.

Bluecurve supplies a well-written user manual that takes you through a logical progression of what the product is and how to use it. Screen shots and diagrams that describe the architecture and components of Dynameasure supplement the discussion of concepts and definitions. You can find complete instructions for the installation and use of the different components, even step-by-step instructions for running a File Services sample test. I highly recommend you thoroughly study Chapter 9, "Testing Strategies," before you try to use the product. The chapter details how to locate bottlenecks, the characteristics of workloads, and how to select the data set and tests to provide a meaningful performance evaluation. Another must-read chapter is Chapter 8, "Analyzing Test Results." Once you've run a test, this chapter will help you sort, filter, and view the results. You'll also find out how to print reports to help you zero in on network problems.

The software includes online Help files that follow Microsoft's format. The Dynameasure Demo CD-ROM contains technical data and a new user tutorial, which I found useful. The tutorial provides an excellent explanation of the software components, and it steps you through configuring and running a successful test.