Developer Guide

  • 2021.1
  • 11/03/2021
  • Public
Contents

When to Use the Data Streams Optimizer

Intel provides a tuning strategy to meet real-time application requirements. Tuning is divided into the following categories:
  • System software tuning
  • Platform power management tuning
  • Intel® TCC features tuning
  • Fabric tuning
Different types of tuning have different effects on latency. The term “latency” refers to the duration of time between two events. It can mean any type of latency: I/O latency, buffer access latency, and the sum of these and others— network packet in to network packet out (cycle time). Use cases with more relaxed requirements need less tuning to meet their latency requirements, while use cases with stricter requirements necessitate substantial effort in tuning.
When tuning the platform, one should address higher-impact tuning first (system software tuning), then work down to lower-impact tuning until the requirements are satisfied. Types of tuning that are lower on the pyramid are more complex and incur higher penalties to concurrent workloads than those higher on the pyramid. However, they may unlock the best possible real-time performance when enabled and used in combination with the higher levels of tuning.
System software, such as the OS and drivers, has the highest impact on real-time performance. System software tuning is described in the Real-Time Tuning Guide, and is not configured by the data streams optimizer.
It is advisable to try Intel provided system software comprised of the board support package (BSP) with real-time optimizations and reference BIOS with Intel® TCC Mode first. This “out of the box” tuning configuration is capable of meeting a certain level of real-time performance and provides baseline tuning of the top three categories in the tuning pyramid: system software tuning, platform power management tuning, and Intel® TCC features tuning. If it does not meet your needs, move on to the more advanced level of tuning possible with the data streams optimizer which provides a finer granularity of tuning and affects platform power management tuning, Intel® TCC features tuning, and is the only way to access fabric tuning.
To summarize:
Tuning Category
Product
System Software Tuning
BSP with real-time optimizations
Platform Power Management Tuning
Out-of-the-box tuning: BSP with real-time optimizations, Intel® TCC Mode in BIOS
Advanced tuning: Data streams optimizer
Intel® TCC Features Tuning
Out-of-the-box tuning: BSP with real-time optimizations, Intel® TCC Mode in BIOS
Advanced tuning: Data streams optimizer
Fabric Tuning
Data streams optimizer
Other Intel® TCC Tools capabilities, for example, cache configurator and cache allocation library, contribute to Intel® TCC features tuning. They are described elsewhere in this guide. Currently, cache allocation library and data streams optimizer cannot be used together. This is because RTCM, an underlying component of cache allocation library, must be disabled before using the data streams optimizer for the first time and must remain disabled afterward. For more details, see Real-Time Configuration Manager (RTCM). If you combine RTCM and data streams optimizer, you may experience system hang and various errors due to offline cores. To resolve the errors, you may need to reflash the BIOS. For more details, see Troubleshooting.

Product and Performance Information

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Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.