koushikbillakanti-amd
67 lines
2.2 KiB
Markdown
67 lines
2.2 KiB
Markdown
---
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myst:
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html_meta:
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"description lang=en": "AMD SMI guide for setting performance determinism."
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"keywords": "system, management, interface, performance, determinism, clock, frequency, gfxclk, benchmark"
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---
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# Performance determinism
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Performance determinism mode enables consistent GPU performance by enforcing a fixed maximum GFXCLK
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(graphics clock) frequency. This prevents clock frequency variations when running the same workload
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across different GPUs, making it useful for benchmarking and performance analysis.
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## How it works
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When enabled, performance determinism sets a user-defined SoftMax limit for the GFXCLK frequency.
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This prevents the GFXCLK PLL from stretching during workload execution, minimizing performance
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variation. The GPU performance level changes to `DETERMINISM` when this mode is active.
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## Supported hardware
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Performance determinism is supported on AMD Instinct MI200 series and AMD Radeon RX 7000 series
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(RDNA 3) GPUs. Support may vary by ASIC -- MI300 series GPUs may not support this feature.
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## From concept to action
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AMD SMI provides tools to enable and manage performance determinism mode.
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:::::{tab-set}
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::::{tab-item} C/C++
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The AMD SMI library provides APIs to enable performance determinism and query the current
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performance level.
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See [Clock, Power, and Performance Control](/doxygen/docBin/html/group__tagClkPowerPerfControl) for
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available APIs.
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::::
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::::{tab-item} Python
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See related APIs:
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- [](/reference/amdsmi-py-api.md#amdsmi_set_gpu_perf_determinism_mode)
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- [](/reference/amdsmi-py-api.md#amdsmi_get_gpu_perf_level)
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- [](/reference/amdsmi-py-api.md#amdsmi_set_gpu_perf_level)
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::::
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::::{tab-item} amd-smi CLI
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See [`amd-smi set --help`](/how-to/amdsmi-cli-tool.md#amd-smi-set) and
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[`amd-smi reset --help`](/how-to/amdsmi-cli-tool.md#amd-smi-reset) for details and available options.
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```shell
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# Enable performance determinism with GFXCLK set to 1900 MHz
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amd-smi set --perf-determinism 1900
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# Disable performance determinism
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amd-smi reset --perf-determinism
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# Query current performance level
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amd-smi metric --perf-level
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```
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::::
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:::::
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## Further reading
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- [PowerPlay (Linux kernel)](https://docs.kernel.org/gpu/amdgpu/driver-misc.html#powerplay)
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- [AMDGPU Documentation](https://docs.kernel.org/gpu/amdgpu/index.html)
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