RISC-V Capacity and Bandwidth Controller QoS Register Interface

This document is capturing discussions at the CMQRI TG and attempts to document the baseline. This is not official specification and everything in this document may change.

Quality of Service (QoS) is the minimal end-to-end performance that is guaranteed in advance by a service level agreement (SLA) to an application.

System software needs additional tools to control interference to an application and thereby reduce the variability in performance experienced by one application due to other application’s cache capacity usage, memory bandwidth usage, interconnect bandwidth usage, power usage, etc. through a capacity and bandwidth allocation capability.

Effective use of the capacity and bandwidth allocation capability requires hardware to provide a capacity and bandwidth monitoring capability by which the resource requirements of an application needed to meet a certain performance goal can be characterized.

License

This work is licensed under a Creative Commons Attribution 4.0 International License (CC-BY-4.0). See the LICENSE file for details.

Contributors

Contributors to this specification are contained in the contributors file.

For instructions on how to contribute please see the CONTRIBUTING file.

Dependencies

This project is built using AsciiDoctor (Ruby). The repository has been setup to build the PDF on checkin using GitHub actions. Workflow dependencies are located in the dependencies directory.

For more information on AsciiDoctor, specification guidelines, or building locally, see the RISC-V Documentation Developer Guide.

Cloning the project

This project uses GitHub Submodules to include the RISC-V docs-resources project to achieve a common look and feel.

When cloning this repository for the first time, you must either use git clone --recurse-submodules or execute git submodule init and git submodule update after the clone to populate the docs-resources directory. Failure to clone the submodule, will result in the PDF build fail with an error message like the following:

$ make
asciidoctor-pdf \
-a toc \
-a compress \
-a pdf-style=docs-resources/themes/riscv-pdf.yml \
-a pdf-fontsdir=docs-resources/fonts \
--failure-level=ERROR \
-o profiles.pdf profiles.adoc
asciidoctor: ERROR: could not locate or load the built-in pdf theme `docs-resources/themes/riscv-pdf.yml'; reverting to default theme
No such file or directory - notoserif-regular-subset.ttf not found in docs-resources/fonts
  Use --trace for backtrace
make: *** [Makefile:7: profiles.pdf] Error 1

Building the document

The final specification form of PDF can be generated using the make command.