CrossfireAPI11

The CrossfireAPI11 sample demonstrates how to use the explicit Crossfire™ application programming interface (API).

View Crossfire API 11 sample on GitHub View Crossfire API 11 sample documentation

This driver extension provides the ability to control resource transfers between GPUs in Crossfire configuration in DirectX® 11. This allows improved performance in multi-GPU configurations.

The CrossfireAPI11 sample shows how the Crossfire API is used in the context of shadow caching.

The sample shows:

How to use different transfer modes with the Crossfire API.
How to reduce contentions using 2-step transfers.
How different shadow map layouts affect Crossfire performance.
How different shadow update schemes affect Crossfire performance.

The CrossfireAPI11 sample also comes with an extensive guide for multi-GPU: the AMD Crossfire guide for Direct3D® 11 applications. It describes the Crossfire implementation in AMD drivers and documents the Crossfire API extensions.

The CrossfireAPI11 sample uses the ShadowFX library.

ShadowFX

ShadowFX library provides a scalable GCN-optimized solution for deferred shadow filtering. It supports uniform and contact hardening shadow (CHS) kernels.

The Crossfire API driver extension is accessed through the AMD GPU Services (AGS) library.

AMD GPU Services (AGS) Library

The AMD GPU Services (AGS) library provides software developers with the ability to query AMD GPU software and hardware state information that is not normally available through standard operating systems or graphics APIs.

Requirements

AMD Radeon™ GCN-based GPU (HD 7000 series or newer).
64-bit Windows® 7 (SP1 with the Platform Update), Windows® 8.1, or Windows® 10.
Visual Studio® 2012, Visual Studio® 2013, or Visual Studio® 2015.