What SPECviewperf™ Does and Doesn't Do

Nearly all benchmarks are designed for a specific purpose. Quite often, however, users broaden that purpose beyond what the benchmark is designed to do, or in some cases they assume the benchmark can't do something that it actually can do. The SPECviewperf benchmark is no different: it has been both overextended and under-appreciated, sometimes reducing its overall value to the user. Here is a closer look at SPECviewperf: what it is and what it can and can't do.

SPECviewperf measures the 3D rendering performance of systems running under OpenGL. The SPECopcSM project group has worked with independent software vendors (ISVs) to obtain tests, data sets and weights that constitute what is called a viewset. Each viewset represents the graphics rendering portion of an actual application. The ISVs that develop SPECopc viewsets have provided percentage weights for each test for which a performance number is reported. ISVs have defined these percentages to indicate the relative importance of a test within the overall application.

SPECviewperf offers the following characteristics:

Several factors make SPECviewperf unique from other benchmarks:

What SPECviewperf Measures

SPECviewperf measures performance for the following entities:

The Five-Step Program

SPECviewperf is not a single-number benchmark. In order to use it to its fullest advantage, ISVs and users need to relate the benchmark to their actual applications. Here are the five steps recommended for using SPECviewperf effectively:
  1. Identify software code paths that are important to the application.
  2. Identify the primitives used within the application.
  3. Select datasets that are most appropriate to the application. The datasets should reflect the level of geometry and rasterization found in the application.
  4. Identify attributes and the level at which they are applied (per vertex, per primitive or per frame).
  5. Assign a weight to each path based on the percentage of time in each path and the importance of the path to the application.

What SPECviewperf Can't Do

Although SPECviewperf is a good tool for measuring OpenGL performance as it relates to applications, like all benchmarks it has limitations. Most important of these is that it cannot be used to compare performance across different application programming interfaces (APIs). Also, it does not run itself; users must participate in the benchmarking process. When testing and reporting results, SPECviewperf does not account for the following key factors:

Continued Improvements

Development of SPECviewperf within the SPECopc group is an ongoing process, with future enhancements designed to address key graphics applications issues not covered by the current benchmark.