Runtime Configuration

SwiftShader provides a simple configuration mechanism based on a configuration file to control a variety of runtime options without needing to re-compile from source.

Configuration file

SwiftShader looks for a file named SwiftShader.ini (case-sensitive) in the working directory. At startup, SwiftShader reads this file, if it exists, and sets the options specified in it.

The configuration file syntax is a series of key-value pairs, divided into sections. The following example shows three key-value pairs in two sections (ThreadCount and AffinityMask in the [Processor] section, and EnableSpirvProfiling in the [Profiler] section):


# Comment

The syntax rules are as follows:

  • Sections are defined via a name in brackets, e.g. [Processor].
  • Key-value pairs are in the format Key=Value.
  • Keys are always strings, while values can be strings, booleans or integers depending on the semantics of the option:
    • For integer options, both decimal and hexademical values are supported.
    • For boolean options, both decimal (1 and 0) and alphabetical (true and false) values are supported.
  • Comments are supported through the use of the # character at the beginning of a line.


Refer to the SwiftConfig.hpp header for an up-to-date overview of available options.