nvidia-smi -ac equivalent in NVML

Question

I learnt than nvidia-smi -ac can be used to change the clock rate of GPU cores and memory. Is nvidia-smi built upon the NVML library? What is its equivalent in NVML since I checked the document

http://cyber.sibsutis.ru:82/GPGPU/sdk/CUDA_TOOLKIT/nvml.pdf

but could only see the API's which are used to get the values of clock rates rather than setting them?

Thanks

Answer 1

Yes, nvidia-smi is built on the NVML library.

According to the latest nvml api documentation available here (which is linked from the site I previously suggested to you here) The "Set Application Clocks" command is supported on Tesla K10 and K20 GPUs (page 6). I believe it is also supported on "Kepler" members of the Quadro family, such as Quadro K5000.

If you have a Tesla K10, K20, or K20X GPU, the Set Application Clocks command is described on p68, which I am also reproducing here for convenience:

7.12.2.2 nvmlReturn_t DECLDIR nvmlDeviceSetApplicationsClocks (nvmlDevice_t device, unsigned int
memClockMHz, unsigned int graphicsClockMHz)

Set clocks that applications will lock to.
Sets the clocks that compute and graphics applications will be running at. e.g. CUDA driver requests these clocks
during context creation which means this property defines clocks at which CUDA applications will be running unless
some overspec event occurs (e.g. over power, over thermal or external HW brake).
Can be used as a setting to request constant performance.
For Tesla ™products, and Quadro ®products from the Kepler family. Requires root/admin permissions.
See nvmlDeviceGetSupportedMemoryClocks and nvmlDeviceGetSupportedGraphicsClocks for details on how to list
available clocks combinations.
After system reboot or driver reload applications clocks go back to their default value.

Parameters:
device The identifier of the target device
memClockMHz Requested memory clock in MHz
graphicsClockMHz Requested graphics clock in MHz

Returns:
• NVML_SUCCESS if new settings were successfully set
• NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized
• NVML_ERROR_INVALID_ARGUMENT if device is invalid or memClockMHz and graphicsClockMHz is
not a valid clock combination
• NVML_ERROR_NO_PERMISSION if the user doesn’t have permission to perform this operation
• NVML_ERROR_NOT_SUPPORTED if the device doesn’t support this feature
• NVML_ERROR_UNKNOWN on any unexpected error