AMDGPU Increasing Fragment Size For Performance
Christian König of AMD yesterday sent out an AMDGPU kernel patch for boosting the default fragment size for GCN graphics cards pre-Vega.
The patch is quite trivial and is for boosting the default fragment size from 64KB to 2MB, similar to the move made with the latest Vega GPUs. This change is for GFX6/GFX7/GFX8 graphics processors or basically all the GCN cards prior to Vega "GFX9".
König has confirmed this should help the performance in some instances. "When you have an application which uses chunks of at least 2MB memory the gain is larger when you select 2MB then when you select 64KB in hardware. But the difference is barely measurable."
With it being too late to change for 4.14, the changeover will presumably happen with Linux 4.15.
The patch is quite trivial and is for boosting the default fragment size from 64KB to 2MB, similar to the move made with the latest Vega GPUs. This change is for GFX6/GFX7/GFX8 graphics processors or basically all the GCN cards prior to Vega "GFX9".
König has confirmed this should help the performance in some instances. "When you have an application which uses chunks of at least 2MB memory the gain is larger when you select 2MB then when you select 64KB in hardware. But the difference is barely measurable."
With it being too late to change for 4.14, the changeover will presumably happen with Linux 4.15.
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