NVML. Reference Manual (vR575 | June 2025)

Modules

‣ NVML_ERROR_NOT_SUPPORTED if this is not an S-class product

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the fan speed readings for the unit.

For S-class products.

See nvmlUnitFanSpeeds_t for details on available fan speed info.

nvmlReturn_t nvmlUnitGetDevices (nvmlUnit_t unit,

unsigned int *deviceCount, nvmlDevice_t *devices)

Parameters

unit

The identifier of the target unit

deviceCount

Reference in which to provide the devices array size, and to return the number of

attached GPU devices

devices

Reference in which to return the references to the attached GPU devices

Returns

‣ NVML_SUCCESS if deviceCount and devices have been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INSUFFICIENT_SIZE if deviceCount indicates that the devices

array is too small

‣ NVML_ERROR_INVALID_ARGUMENT if unit is invalid, either of deviceCount or

devices is NULL

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the set of GPU devices that are attached to the specified unit.

For S-class products.

The deviceCount argument is expected to be set to the size of the input devices array.

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4.16. Device Queries

This chapter describes that queries that NVML can perform against each device. In each

case the device is identified with an nvmlDevice_t handle. This handle is obtained by

calling one of nvmlDeviceGetHandleByIndex_v2(), nvmlDeviceGetHandleBySerial(),

nvmlDeviceGetHandleByPciBusId_v2(). or nvmlDeviceGetHandleByUUID().

struct nvmlTemperature_v1_t

CPU and Memory Affinity

nvmlReturn_t nvmlDeviceGetCount_v2 (unsigned int

*deviceCount)

Parameters

deviceCount

Reference in which to return the number of accessible devices

Returns

‣ NVML_SUCCESS if deviceCount has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if deviceCount is NULL

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the number of compute devices in the system. A compute device is a single

GPU.

For all products.

Note: New nvmlDeviceGetCount_v2 (default in NVML 5.319) returns count

of all devices in the system even if nvmlDeviceGetHandleByIndex_v2 returns

NVML_ERROR_NO_PERMISSION for such device. Update your code to handle this

error, or use NVML 4.304 or older nvml header file. For backward binary compatibility

reasons _v1 version of the API is still present in the shared library. Old _v1 version of

nvmlDeviceGetCount doesn't count devices that NVML has no permission to talk to.

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nvmlReturn_t nvmlDeviceGetAttributes_v2

(nvmlDevice_t device, nvmlDeviceAttributes_t

*attributes)

Parameters

device

NVML device handle

attributes

Device attributes

Returns

‣ NVML_SUCCESS if device attributes were successfully retrieved

‣ NVML_ERROR_INVALID_ARGUMENT if device handle is invalid

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_NOT_SUPPORTED if this query is not supported by the device

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Get attributes (engine counts etc.) for the given NVML device handle.

This API currently only supports MIG device handles.

For Ampere or newer fully supported devices. Supported on Linux only.

nvmlReturn_t nvmlDeviceGetHandleByIndex_v2

(unsigned int index, nvmlDevice_t *device)

Parameters

index

The index of the target GPU, >= 0 and < accessibleDevices

device

Reference in which to return the device handle

Returns

‣ NVML_SUCCESS if device has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if index is invalid or device is NULL

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‣ NVML_ERROR_INSUFFICIENT_POWER if any attached devices have improperly

attached external power cables

‣ NVML_ERROR_NO_PERMISSION if the user doesn't have permission to talk to this

device

‣ NVML_ERROR_IRQ_ISSUE if NVIDIA kernel detected an interrupt issue with the

attached GPUs

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Acquire the handle for a particular device, based on its index.

For all products.

Valid indices are derived from the accessibleDevices count returned by

nvmlDeviceGetCount_v2(). For example, if accessibleDevices is 2 the valid indices are 0

and 1, corresponding to GPU 0 and GPU 1.

The order in which NVML enumerates devices has no guarantees of consistency

between reboots. For that reason it is recommended that devices be looked

up by their PCI ids or UUID. See nvmlDeviceGetHandleByUUID() and

nvmlDeviceGetHandleByPciBusId_v2().

Note: The NVML index may not correlate with other APIs, such as the CUDA device

index.

Starting from NVML 5, this API causes NVML to initialize the target GPU NVML may

initialize additional GPUs if:

‣ The target GPU is an SLI slave

Note: New nvmlDeviceGetCount_v2 (default in NVML 5.319) returns count

of all devices in the system even if nvmlDeviceGetHandleByIndex_v2 returns

NVML_ERROR_NO_PERMISSION for such device. Update your code to handle this

error, or use NVML 4.304 or older nvml header file. For backward binary compatibility

reasons _v1 version of the API is still present in the shared library. Old _v1 version of

nvmlDeviceGetCount doesn't count devices that NVML has no permission to talk to.

This means that nvmlDeviceGetHandleByIndex_v2 and _v1 can return different devices

for the same index. If you don't touch macros that map old (_v1) versions to _v2 versions

at the top of the file you don't need to worry about that.

See also:

nvmlDeviceGetIndex

nvmlDeviceGetCount

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nvmlReturn_t nvmlDeviceGetHandleBySerial (const char

*serial, nvmlDevice_t *device)

Parameters

serial

The board serial number of the target GPU

device

Reference in which to return the device handle

Returns

‣ NVML_SUCCESS if device has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if serial is invalid, device is NULL or more

than one device has the same serial (dual GPU boards)

‣ NVML_ERROR_NOT_FOUND if serial does not match a valid device on the system

‣ NVML_ERROR_INSUFFICIENT_POWER if any attached devices have improperly

attached external power cables

‣ NVML_ERROR_IRQ_ISSUE if NVIDIA kernel detected an interrupt issue with the

attached GPUs

‣ NVML_ERROR_GPU_IS_LOST if any GPU has fallen off the bus or is otherwise

inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Acquire the handle for a particular device, based on its board serial number.

For Fermi or newer fully supported devices.

This number corresponds to the value printed directly on the board, and to the value

returned by nvmlDeviceGetSerial().

Deprecated Since more than one GPU can exist on a single board this function is

deprecated in favor of nvmlDeviceGetHandleByUUID. For dual GPU boards this

function will return NVML_ERROR_INVALID_ARGUMENT.

Starting from NVML 5, this API causes NVML to initialize the target GPU NVML may

initialize additional GPUs as it searches for the target GPU

See also:

nvmlDeviceGetSerial

nvmlDeviceGetHandleByUUID

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nvmlReturn_t nvmlDeviceGetHandleByUUID (const char

*uuid, nvmlDevice_t *device)

Parameters

uuid

The UUID of the target GPU or MIG instance

device

Reference in which to return the device handle or MIG device handle

Returns

‣ NVML_SUCCESS if device has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if uuid is invalid or device is null

‣ NVML_ERROR_NOT_FOUND if uuid does not match a valid device on the system

‣ NVML_ERROR_INSUFFICIENT_POWER if any attached devices have improperly

attached external power cables

‣ NVML_ERROR_IRQ_ISSUE if NVIDIA kernel detected an interrupt issue with the

attached GPUs

‣ NVML_ERROR_GPU_IS_LOST if any GPU has fallen off the bus or is otherwise

inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Acquire the handle for a particular device, based on its globally unique immutable

UUID (in ASCII format) associated with each device.

For all products.

Starting from NVML 5, this API causes NVML to initialize the target GPU NVML may

initialize additional GPUs as it searches for the target GPU

See also:

nvmlDeviceGetUUID

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nvmlReturn_t nvmlDeviceGetHandleByUUIDV (const

nvmlUUID_t *uuid, nvmlDevice_t *device)

Parameters

uuid

The UUID of the target GPU or MIG instance

device

Reference in which to return the device handle or MIG device handle

Returns

‣ NVML_SUCCESS if device has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if uuid is invalid, device is null or uuid-

>type is invalid

‣ NVML_ERROR_ARGUMENT_VERSION_MISMATCH if the provided version is

invalid/unsupported

‣ NVML_ERROR_NOT_FOUND if uuid does not match a valid device on the system

‣ NVML_ERROR_GPU_IS_LOST if any GPU has fallen off the bus or is otherwise

inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Acquire the handle for a particular device, based on its globally unique immutable

UUID (in either ASCII or binary format) associated with each device. See

nvmlUUID_v1_t for more information on the UUID struct. The caller must set the

appropriate version prior to calling this API.

For all products.

This API causes NVML to initialize the target GPU NVML may initialize additional

GPUs as it searches for the target GPU

nvmlReturn_t nvmlDeviceGetHandleByPciBusId_v2

(const char *pciBusId, nvmlDevice_t *device)

Parameters

pciBusId

The PCI bus id of the target GPU Accept the following formats (all numbers in

hexadecimal): domain:bus:device.function in format x:x:x.x domain:bus:device in

format x:x:x bus:device.function in format x:x.x

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device

Reference in which to return the device handle

Returns

‣ NVML_SUCCESS if device has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if pciBusId is invalid or device is NULL

‣ NVML_ERROR_NOT_FOUND if pciBusId does not match a valid device on the

system

‣ NVML_ERROR_INSUFFICIENT_POWER if the attached device has improperly

attached external power cables

‣ NVML_ERROR_NO_PERMISSION if the user doesn't have permission to talk to this

device

‣ NVML_ERROR_IRQ_ISSUE if NVIDIA kernel detected an interrupt issue with the

attached GPUs

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Acquire the handle for a particular device, based on its PCI bus id.

For all products.

This value corresponds to the nvmlPciInfo_t::busId returned by

nvmlDeviceGetPciInfo_v3().

Starting from NVML 5, this API causes NVML to initialize the target GPU NVML may

initialize additional GPUs if:

‣ The target GPU is an SLI slave

NVML 4.304 and older version of nvmlDeviceGetHandleByPciBusId"_v1" returns

NVML_ERROR_NOT_FOUND instead of NVML_ERROR_NO_PERMISSION.

nvmlReturn_t nvmlDeviceGetName (nvmlDevice_t

device, char *name, unsigned int length)

Parameters

device

The identifier of the target device

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name

Reference in which to return the product name

length

The maximum allowed length of the string returned in name

Returns

‣ NVML_SUCCESS if name has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or name is NULL

‣ NVML_ERROR_INSUFFICIENT_SIZE if length is too small

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the name of this device.

For all products.

The name is an alphanumeric string that denotes a particular product, e.g. Tesla

C2070. It will not exceed 96 characters in length (including the NULL terminator). See

nvmlConstants::NVML_DEVICE_NAME_V2_BUFFER_SIZE.

When used with MIG device handles the API returns MIG device names which can be

used to identify devices based on their attributes.

nvmlReturn_t nvmlDeviceGetBrand (nvmlDevice_t

device, nvmlBrandType_t *type)

Parameters

device

The identifier of the target device

type

Reference in which to return the product brand type

Returns

‣ NVML_SUCCESS if name has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or type is NULL

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

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‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the brand of this device.

For all products.

The type is a member of nvmlBrandType_t defined above.

nvmlReturn_t nvmlDeviceGetIndex (nvmlDevice_t

device, unsigned int *index)

Parameters

device

The identifier of the target device

index

Reference in which to return the NVML index of the device

Returns

‣ NVML_SUCCESS if index has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or index is NULL

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the NVML index of this device.

For all products.

Valid indices are derived from the accessibleDevices count returned by

nvmlDeviceGetCount_v2(). For example, if accessibleDevices is 2 the valid indices are 0

and 1, corresponding to GPU 0 and GPU 1.

The order in which NVML enumerates devices has no guarantees of consistency

between reboots. For that reason it is recommended that devices be looked up

by their PCI ids or GPU UUID. See nvmlDeviceGetHandleByPciBusId_v2() and

nvmlDeviceGetHandleByUUID().

When used with MIG device handles this API returns indices that can be passed to

nvmlDeviceGetMigDeviceHandleByIndex to retrieve an identical handle. MIG device

indices are unique within a device.

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Note: The NVML index may not correlate with other APIs, such as the CUDA device

index.

See also:

nvmlDeviceGetHandleByIndex()

nvmlDeviceGetCount()

nvmlReturn_t nvmlDeviceGetSerial (nvmlDevice_t

device, char *serial, unsigned int length)

Parameters

device

The identifier of the target device

serial

Reference in which to return the board/module serial number

length

The maximum allowed length of the string returned in serial

Returns

‣ NVML_SUCCESS if serial has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or serial is NULL

‣ NVML_ERROR_INSUFFICIENT_SIZE if length is too small

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the globally unique board serial number associated with this device's board.

For all products with an inforom.

The serial number is an alphanumeric string that will not exceed 30

characters (including the NULL terminator). This number matches

the serial number tag that is physically attached to the board. See

nvmlConstants::NVML_DEVICE_SERIAL_BUFFER_SIZE.

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nvmlReturn_t nvmlDeviceGetModuleId (nvmlDevice_t

device, unsigned int *moduleId)

Parameters

device

The identifier of the target device

moduleId

Unique identifier for the GPU module

Returns

‣ NVML_SUCCESS if moduleId has been successfully retrieved

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device or moduleId is invalid

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Get a unique identifier for the device module on the baseboard

This API retrieves a unique identifier for each GPU module that exists on a given

baseboard. For non-baseboard products, this ID would always be 0.

nvmlReturn_t nvmlDeviceGetC2cModeInfoV

(nvmlDevice_t device, nvmlC2cModeInfo_v1_t

*c2cModeInfo)

Parameters

device

The identifier of the target device

c2cModeInfo

Output struct containing the device's C2C Mode info

Returns

‣ NVML_SUCCESS if C2C Mode Infor query is successful

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or serial is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

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Description

Retrieves the Device's C2C Mode information

nvmlReturn_t nvmlDeviceGetTopologyCommonAncestor

(nvmlDevice_t device1, nvmlDevice_t device2,

nvmlGpuTopologyLevel_t *pathInfo)

Parameters

device1

The identifier of the first device

device2

The identifier of the second device

pathInfo

A nvmlGpuTopologyLevel_t that gives the path type

Returns

‣ NVML_SUCCESS if pathInfo has been set

‣ NVML_ERROR_INVALID_ARGUMENT if device1, or device2 is invalid, or

pathInfo is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device or OS does not support this

feature

‣ NVML_ERROR_UNKNOWN an error has occurred in underlying topology

discovery

Description

Retrieve the common ancestor for two devices For all products. Supported on Linux

only.

nvmlReturn_t nvmlDeviceGetTopologyNearestGpus

(nvmlDevice_t device, nvmlGpuTopologyLevel_t level,

unsigned int *count, nvmlDevice_t *deviceArray)

Parameters

device

The identifier of the first device

level

The nvmlGpuTopologyLevel_t level to search for other GPUs

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count

When zero, is set to the number of matching GPUs such that deviceArray can be

malloc'd. When non-zero, deviceArray will be filled with count number of device

handles.

deviceArray

An array of device handles for GPUs found at level

Returns

‣ NVML_SUCCESS if deviceArray or count (if initially zero) has been set

‣ NVML_ERROR_INVALID_ARGUMENT if device, level, or count is invalid, or

deviceArray is NULL with a non-zero count

‣ NVML_ERROR_NOT_SUPPORTED if the device or OS does not support this

feature

‣ NVML_ERROR_UNKNOWN an error has occurred in underlying topology

discovery

Description

Retrieve the set of GPUs that are nearest to a given device at a specific interconnectivity

level For all products. Supported on Linux only.

nvmlReturn_t nvmlDeviceGetP2PStatus

(nvmlDevice_t device1, nvmlDevice_t device2,

nvmlGpuP2PCapsIndex_t p2pIndex, nvmlGpuP2PStatus_t

*p2pStatus)

Parameters

device1

The first device

device2

The second device

p2pIndex

p2p Capability Index being looked for between device1 and device2

p2pStatus

Reference in which to return the status of the p2pIndex between device1 and device2

Returns

‣ NVML_SUCCESS if p2pStatus has been populated

‣ NVML_ERROR_INVALID_ARGUMENT if device1 or device2 or p2pIndex is

invalid or p2pStatus is NULL

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‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve the status for a given p2p capability index between a given pair of GPU

nvmlReturn_t nvmlDeviceGetUUID (nvmlDevice_t

device, char *uuid, unsigned int length)

Parameters

device

The identifier of the target device

uuid

Reference in which to return the GPU UUID

length

The maximum allowed length of the string returned in uuid

Returns

‣ NVML_SUCCESS if uuid has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or uuid is NULL

‣ NVML_ERROR_INSUFFICIENT_SIZE if length is too small

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the globally unique immutable UUID associated with this device, as a 5 part

hexadecimal string, that augments the immutable, board serial identifier.

For all products.

The UUID is a globally unique identifier. It is the only available identifier for pre-

Fermi-architecture products. It does NOT correspond to any identifier printed on the

board. It will not exceed 96 characters in length (including the NULL terminator). See

nvmlConstants::NVML_DEVICE_UUID_V2_BUFFER_SIZE.

When used with MIG device handles the API returns globally unique UUIDs which

can be used to identify MIG devices across both GPU and MIG devices. UUIDs are

immutable for the lifetime of a MIG device.

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nvmlReturn_t nvmlDeviceGetMinorNumber

(nvmlDevice_t device, unsigned int *minorNumber)

Parameters

device

The identifier of the target device

minorNumber

Reference in which to return the minor number for the device

Returns

‣ NVML_SUCCESS if the minor number is successfully retrieved

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or minorNumber is

NULL

‣ NVML_ERROR_NOT_SUPPORTED if this query is not supported by the device

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves minor number for the device. The minor number for the device is such that the

Nvidia device node file for each GPU will have the form /dev/nvidia[minor number].

For all products. Supported only for Linux

nvmlReturn_t nvmlDeviceGetBoardPartNumber

(nvmlDevice_t device, char *partNumber, unsigned int

length)

Parameters

device

Identifier of the target device

partNumber

Reference to the buffer to return

length

Length of the buffer reference

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Returns

‣ NVML_SUCCESS if partNumber has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_NOT_SUPPORTED if the needed VBIOS fields have not been filled

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or serial is NULL

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the the device board part number which is programmed into the board's

InfoROM

For all products.

nvmlReturn_t nvmlDeviceGetInforomVersion

(nvmlDevice_t device, nvmlInforomObject_t object,

char *version, unsigned int length)

Parameters

device

The identifier of the target device

object

The target infoROM object

version

Reference in which to return the infoROM version

length

The maximum allowed length of the string returned in version

Returns

‣ NVML_SUCCESS if version has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if version is NULL

‣ NVML_ERROR_INSUFFICIENT_SIZE if length is too small

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have an infoROM

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

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Description

Retrieves the version information for the device's infoROM object.

For all products with an inforom.

Fermi and higher parts have non-volatile on-board memory for persisting

device info, such as aggregate ECC counts. The version of the data

structures in this memory may change from time to time. It will not

exceed 16 characters in length (including the NULL terminator). See

nvmlConstants::NVML_DEVICE_INFOROM_VERSION_BUFFER_SIZE.

See nvmlInforomObject_t for details on the available infoROM objects.

See also:

nvmlDeviceGetInforomImageVersion

nvmlReturn_t nvmlDeviceGetInforomImageVersion

(nvmlDevice_t device, char *version, unsigned int

length)

Parameters

device

The identifier of the target device

version

Reference in which to return the infoROM image version

length

The maximum allowed length of the string returned in version

Returns

‣ NVML_SUCCESS if version has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if version is NULL

‣ NVML_ERROR_INSUFFICIENT_SIZE if length is too small

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have an infoROM

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the global infoROM image version

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For all products with an inforom.

Image version just like VBIOS version uniquely describes the exact version

of the infoROM flashed on the board in contrast to infoROM object version

which is only an indicator of supported features. Version string will not

exceed 16 characters in length (including the NULL terminator). See

nvmlConstants::NVML_DEVICE_INFOROM_VERSION_BUFFER_SIZE.

See also:

nvmlDeviceGetInforomVersion

nvmlReturn_t

nvmlDeviceGetInforomConfigurationChecksum

(nvmlDevice_t device, unsigned int *checksum)

Parameters

device

The identifier of the target device

checksum

Reference in which to return the infoROM configuration checksum

Returns

‣ NVML_SUCCESS if checksum has been set

‣ NVML_ERROR_CORRUPTED_INFOROM if the device's checksum couldn't be

retrieved due to infoROM corruption

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if checksum is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the checksum of the configuration stored in the device's infoROM.

For all products with an inforom.

Can be used to make sure that two GPUs have the exact same configuration. Current

checksum takes into account configuration stored in PWR and ECC infoROM objects.

Checksum can change between driver releases or when user changes configuration (e.g.

disable/enable ECC)

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nvmlReturn_t nvmlDeviceValidateInforom (nvmlDevice_t

device)

Parameters

device

The identifier of the target device

Returns

‣ NVML_SUCCESS if infoROM is not corrupted

‣ NVML_ERROR_CORRUPTED_INFOROM if the device's infoROM is corrupted

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Reads the infoROM from the flash and verifies the checksums.

For all products with an inforom.

nvmlReturn_t nvmlDeviceGetLastBBXFlushTime

(nvmlDevice_t device, unsigned long long *timestamp,

unsignedlong *durationUs)

Parameters

device

The identifier of the target device

timestamp

The start timestamp of the last BBX Flush

durationUs

The duration (us) of the last BBX Flush

Returns

‣ NVML_SUCCESS if timestamp and durationUs are successfully retrieved

‣ NVML_ERROR_NOT_READY if the BBX object has not been flushed yet

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have an infoROM

Modules

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the timestamp and the duration of the last flush of the BBX (blackbox)

infoROM object during the current run.

For all products with an inforom.

See also:

nvmlDeviceGetInforomVersion

nvmlReturn_t nvmlDeviceGetDisplayMode (nvmlDevice_t

device, nvmlEnableState_t *display)

Parameters

device

The identifier of the target device

display

Reference in which to return the display mode

Returns

‣ NVML_SUCCESS if display has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or display is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the display mode for the device.

For all products.

This method indicates whether a physical display (e.g. monitor) is currently connected

to any of the device's connectors.

See nvmlEnableState_t for details on allowed modes.

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Modules

nvmlReturn_t nvmlDeviceGetDisplayActive

(nvmlDevice_t device, nvmlEnableState_t *isActive)

Parameters

device

The identifier of the target device

isActive

Reference in which to return the display active state

Returns

‣ NVML_SUCCESS if isActive has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or isActive is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the display active state for the device.

For all products.

This method indicates whether a display is initialized on the device. For example

whether X Server is attached to this device and has allocated memory for the screen.

Display can be active even when no monitor is physically attached.

See nvmlEnableState_t for details on allowed modes.

nvmlReturn_t nvmlDeviceGetPersistenceMode

(nvmlDevice_t device, nvmlEnableState_t *mode)

Parameters

device

The identifier of the target device

mode

Reference in which to return the current driver persistence mode

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Modules

Returns

‣ NVML_SUCCESS if mode has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or mode is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the persistence mode associated with this device.

For all products. For Linux only.

When driver persistence mode is enabled the driver software state is not torn down

when the last client disconnects. By default this feature is disabled.

See nvmlEnableState_t for details on allowed modes.

See also:

nvmlDeviceSetPersistenceMode()

nvmlReturn_t nvmlDeviceGetPciInfoExt (nvmlDevice_t

device, nvmlPciInfoExt_t *pci)

Parameters

device

The identifier of the target device

pci

Reference in which to return the PCI info

Returns

‣ NVML_SUCCESS if pci has been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or pci is NULL

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

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Description

Retrieves PCI attributes of this device.

For all products.

See nvmlPciInfoExt_v1_t for details on the available PCI info.

nvmlReturn_t nvmlDeviceGetPciInfo_v3 (nvmlDevice_t

device, nvmlPciInfo_t *pci)

Parameters

device

The identifier of the target device

pci

Reference in which to return the PCI info

Returns

‣ NVML_SUCCESS if pci has been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or pci is NULL

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the PCI attributes of this device.

For all products.

See nvmlPciInfo_t for details on the available PCI info.

nvmlReturn_t nvmlDeviceGetMaxPcieLinkGeneration

(nvmlDevice_t device, unsigned int *maxLinkGen)

Parameters

device

The identifier of the target device

maxLinkGen

Reference in which to return the max PCIe link generation

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Returns

‣ NVML_SUCCESS if maxLinkGen has been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or maxLinkGen is null

‣ NVML_ERROR_NOT_SUPPORTED if PCIe link information is not available

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the maximum PCIe link generation possible with this device and system

I.E. for a generation 2 PCIe device attached to a generation 1 PCIe bus the max link

generation this function will report is generation 1.

For Fermi or newer fully supported devices.

nvmlReturn_t nvmlDeviceGetGpuMaxPcieLinkGeneration

(nvmlDevice_t device, unsigned int *maxLinkGenDevice)

Parameters

device

The identifier of the target device

maxLinkGenDevice

Reference in which to return the max PCIe link generation

Returns

‣ NVML_SUCCESS if maxLinkGenDevice has been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or maxLinkGenDevice

is null

‣ NVML_ERROR_NOT_SUPPORTED if PCIe link information is not available

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the maximum PCIe link generation supported by this device

For Fermi or newer fully supported devices.

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Modules

nvmlReturn_t nvmlDeviceGetMaxPcieLinkWidth

(nvmlDevice_t device, unsigned int *maxLinkWidth)

Parameters

device

The identifier of the target device

maxLinkWidth

Reference in which to return the max PCIe link generation

Returns

‣ NVML_SUCCESS if maxLinkWidth has been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or maxLinkWidth is

null

‣ NVML_ERROR_NOT_SUPPORTED if PCIe link information is not available

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the maximum PCIe link width possible with this device and system

I.E. for a device with a 16x PCIe bus width attached to a 8x PCIe system bus this function

will report a max link width of 8.

For Fermi or newer fully supported devices.

nvmlReturn_t nvmlDeviceGetCurrPcieLinkGeneration

(nvmlDevice_t device, unsigned int *currLinkGen)

Parameters

device

The identifier of the target device

currLinkGen

Reference in which to return the current PCIe link generation

Returns

‣ NVML_SUCCESS if currLinkGen has been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

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‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or currLinkGen is null

‣ NVML_ERROR_NOT_SUPPORTED if PCIe link information is not available

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the current PCIe link generation

For Fermi or newer fully supported devices.

nvmlReturn_t nvmlDeviceGetCurrPcieLinkWidth

(nvmlDevice_t device, unsigned int *currLinkWidth)

Parameters

device

The identifier of the target device

currLinkWidth

Reference in which to return the current PCIe link generation

Returns

‣ NVML_SUCCESS if currLinkWidth has been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or currLinkWidth is

null

‣ NVML_ERROR_NOT_SUPPORTED if PCIe link information is not available

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the current PCIe link width

For Fermi or newer fully supported devices.

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nvmlReturn_t nvmlDeviceGetPcieThroughput

(nvmlDevice_t device, nvmlPcieUtilCounter_t counter,

unsigned int *value)

Parameters

device

The identifier of the target device

counter

The specific counter that should be queried nvmlPcieUtilCounter_t

value

Reference in which to return throughput in KB/s

Returns

‣ NVML_SUCCESS if value has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device or counter is invalid, or value is

NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve PCIe utilization information. This function is querying a byte counter over a

20ms interval and thus is the PCIe throughput over that interval.

For Maxwell or newer fully supported devices.

This method is not supported in virtual machines running virtual GPU (vGPU).

nvmlReturn_t nvmlDeviceGetPcieReplayCounter

(nvmlDevice_t device, unsigned int *value)

Parameters

device

The identifier of the target device

value

Reference in which to return the counter's value

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Returns

‣ NVML_SUCCESS if value has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or value is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve the PCIe replay counter.

For Kepler or newer fully supported devices.

nvmlReturn_t nvmlDeviceGetClockInfo (nvmlDevice_t

device, nvmlClockType_t type, unsigned int *clock)

Parameters

device

The identifier of the target device

type

Identify which clock domain to query

clock

Reference in which to return the clock speed in MHz

Returns

‣ NVML_SUCCESS if clock has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clock is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device cannot report the specified clock

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the current clock speeds for the device.

For Fermi or newer fully supported devices.

See nvmlClockType_t for details on available clock information.

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Modules

nvmlReturn_t nvmlDeviceGetMaxClockInfo

(nvmlDevice_t device, nvmlClockType_t type, unsigned

int *clock)

Parameters

device

The identifier of the target device

type

Identify which clock domain to query

clock

Reference in which to return the clock speed in MHz

Returns

‣ NVML_SUCCESS if clock has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clock is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device cannot report the specified clock

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the maximum clock speeds for the device.

For Fermi or newer fully supported devices.

See nvmlClockType_t for details on available clock information.

On GPUs from Fermi family current P0 clocks (reported by nvmlDeviceGetClockInfo)

can differ from max clocks by few MHz.

nvmlReturn_t nvmlDeviceGetGpcClkVfOffset

(nvmlDevice_t device, int *offset)

Parameters

device

The identifier of the target device

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offset

The retrieved GPCCLK VF offset value

Returns

‣ NVML_SUCCESS if offset has been successfully queried

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or offset is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve the GPCCLK VF offset value

nvmlReturn_t nvmlDeviceGetApplicationsClock

(nvmlDevice_t device, nvmlClockType_t clockType,

unsigned int *clockMHz)

Parameters

device

The identifier of the target device

clockType

Identify which clock domain to query

clockMHz

Reference in which to return the clock in MHz

Returns

‣ NVML_SUCCESS if clockMHz has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clockMHz is NULL

or clockType is invalid

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the current setting of a clock that applications will use unless an overspec

situation occurs. Can be changed using nvmlDeviceSetApplicationsClocks.

For Kepler or newer fully supported devices.

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nvmlReturn_t nvmlDeviceGetDefaultApplicationsClock

(nvmlDevice_t device, nvmlClockType_t clockType,

unsigned int *clockMHz)

Parameters

device

The identifier of the target device

clockType

Identify which clock domain to query

clockMHz

Reference in which to return the default clock in MHz

Returns

‣ NVML_SUCCESS if clockMHz has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clockMHz is NULL

or clockType is invalid

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the default applications clock that GPU boots with or defaults to after

nvmlDeviceResetApplicationsClocks call.

For Kepler or newer fully supported devices.

See also:

nvmlDeviceGetApplicationsClock

143

Modules

nvmlReturn_t nvmlDeviceGetClock (nvmlDevice_t

device, nvmlClockType_t clockType, nvmlClockId_t

clockId, unsigned int *clockMHz)

Parameters

device

The identifier of the target device

clockType

Identify which clock domain to query

clockId

Identify which clock in the domain to query

clockMHz

Reference in which to return the clock in MHz

Returns

‣ NVML_SUCCESS if clockMHz has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clockMHz is NULL

or clockType is invalid

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the clock speed for the clock specified by the clock type and clock ID.

For Kepler or newer fully supported devices.

nvmlReturn_t nvmlDeviceGetMaxCustomerBoostClock

(nvmlDevice_t device, nvmlClockType_t clockType,

unsigned int *clockMHz)

Parameters

device

The identifier of the target device

clockType

Identify which clock domain to query

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clockMHz

Reference in which to return the clock in MHz

Returns

‣ NVML_SUCCESS if clockMHz has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clockMHz is NULL

or clockType is invalid

‣ NVML_ERROR_NOT_SUPPORTED if the device or the clockType on this device

does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the customer defined maximum boost clock speed specified by the given clock

type.

For Pascal or newer fully supported devices.

nvmlReturn_t nvmlDeviceGetSupportedMemoryClocks

(nvmlDevice_t device, unsigned int *count, unsigned int

*clocksMHz)

Parameters

device

The identifier of the target device

count

Reference in which to provide the clocksMHz array size, and to return the number of

elements

clocksMHz

Reference in which to return the clock in MHz

Returns

‣ NVML_SUCCESS if count and clocksMHz have been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or count is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_INSUFFICIENT_SIZE if count is too small (count is set to the

number of required elements)

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‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the list of possible memory clocks that can be used as an argument for

nvmlDeviceSetApplicationsClocks.

For Kepler or newer fully supported devices.

See also:

nvmlDeviceSetApplicationsClocks

nvmlDeviceGetSupportedGraphicsClocks

nvmlReturn_t nvmlDeviceGetSupportedGraphicsClocks

(nvmlDevice_t device, unsigned int memoryClockMHz,

unsigned int *count, unsigned int *clocksMHz)

Parameters

device

The identifier of the target device

memoryClockMHz

Memory clock for which to return possible graphics clocks

count

Reference in which to provide the clocksMHz array size, and to return the number of

elements

clocksMHz

Reference in which to return the clocks in MHz

Returns

‣ NVML_SUCCESS if count and clocksMHz have been populated

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_NOT_FOUND if the specified memoryClockMHz is not a

supported frequency

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clock is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_INSUFFICIENT_SIZE if count is too small

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

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‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the list of possible graphics clocks that can be used as an argument for

nvmlDeviceSetApplicationsClocks.

For Kepler or newer fully supported devices.

See also:

nvmlDeviceSetApplicationsClocks

nvmlDeviceGetSupportedMemoryClocks

nvmlReturn_t nvmlDeviceGetAutoBoostedClocksEnabled

(nvmlDevice_t device, nvmlEnableState_t *isEnabled,

nvmlEnableState_t *defaultIsEnabled)

Parameters

device

The identifier of the target device

isEnabled

Where to store the current state of Auto Boosted clocks of the target device

defaultIsEnabled

Where to store the default Auto Boosted clocks behavior of the target device that the

device will revert to when no applications are using the GPU

Returns

‣ NVML_SUCCESS If isEnabled has been been set with the Auto Boosted clocks state

of device

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or isEnabled is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support Auto Boosted

clocks

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve the current state of Auto Boosted clocks on a device and store it in isEnabled

For Kepler or newer fully supported devices.

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Auto Boosted clocks are enabled by default on some hardware, allowing the GPU to run

at higher clock rates to maximize performance as thermal limits allow.

On Pascal and newer hardware, Auto Aoosted clocks are controlled through application

clocks. Use nvmlDeviceSetApplicationsClocks and nvmlDeviceResetApplicationsClocks

to control Auto Boost behavior.

nvmlReturn_t nvmlDeviceGetFanSpeed (nvmlDevice_t

device, unsigned int *speed)

Parameters

device

The identifier of the target device

speed

Reference in which to return the fan speed percentage

Returns

‣ NVML_SUCCESS if speed has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or speed is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have a fan

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the intended operating speed of the device's fan.

Note: The reported speed is the intended fan speed. If the fan is physically blocked and

unable to spin, the output will not match the actual fan speed.

For all discrete products with dedicated fans.

The fan speed is expressed as a percentage of the product's maximum noise tolerance

fan speed. This value may exceed 100% in certain cases.

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Modules

nvmlReturn_t nvmlDeviceGetFanSpeed_v2

(nvmlDevice_t device, unsigned int fan, unsigned int

*speed)

Parameters

device

The identifier of the target device

fan

The index of the target fan, zero indexed.

speed

Reference in which to return the fan speed percentage

Returns

‣ NVML_SUCCESS if speed has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, fan is not an acceptable

index, or speed is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have a fan or is newer

than Maxwell

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the intended operating speed of the device's specified fan.

Note: The reported speed is the intended fan speed. If the fan is physically blocked and

unable to spin, the output will not match the actual fan speed.

For all discrete products with dedicated fans.

The fan speed is expressed as a percentage of the product's maximum noise tolerance

fan speed. This value may exceed 100% in certain cases.

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Modules

nvmlReturn_t nvmlDeviceGetFanSpeedRPM

(nvmlDevice_t device, nvmlFanSpeedInfo_t *fanSpeed)

Parameters

device

The identifier of the target device

fanSpeed

Structure specifying the index of the target fan (input) and retrieved fan speed value

(output)

Returns

‣ NVML_SUCCESS If everything worked

‣ NVML_ERROR_UNINITIALIZED If the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT If device is invalid, fan is not an acceptable

index, or speed is NULL

‣ NVML_ERROR_ARGUMENT_VERSION_MISMATCH If the provided version is

invalid/unsupported

‣ NVML_ERROR_NOT_SUPPORTED If the device does not support this feature

Description

Retrieves the intended operating speed in rotations per minute (RPM) of the device's

specified fan.

For Maxwell or newer fully supported devices.

For all discrete products with dedicated fans.

Note: The reported speed is the intended fan speed. If the fan is physically blocked and

unable to spin, the output will not match the actual fan speed.

nvmlReturn_t nvmlDeviceGetTargetFanSpeed

(nvmlDevice_t device, unsigned int fan, unsigned int

*targetSpeed)

Parameters

device

The identifier of the target device

fan

The index of the target fan, zero indexed.

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targetSpeed

Reference in which to return the fan speed percentage

Returns

‣ NVML_SUCCESS if speed has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, fan is not an acceptable

index, or speed is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have a fan or is newer

than Maxwell

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the intended target speed of the device's specified fan.

Normally, the driver dynamically adjusts the fan based on the needs of the GPU. But

when user set fan speed using nvmlDeviceSetFanSpeed_v2, the driver will attempt to

make the fan achieve the setting in nvmlDeviceSetFanSpeed_v2. The actual current

speed of the fan is reported in nvmlDeviceGetFanSpeed_v2.

For all discrete products with dedicated fans.

The fan speed is expressed as a percentage of the product's maximum noise tolerance

fan speed. This value may exceed 100% in certain cases.

nvmlReturn_t nvmlDeviceGetMinMaxFanSpeed

(nvmlDevice_t device, unsigned int *minSpeed, unsigned

int *maxSpeed)

Parameters

device

The identifier of the target device

minSpeed

The minimum speed allowed to set

maxSpeed

The maximum speed allowed to set

Description

Retrieves the min and max fan speed that user can set for the GPU fan.

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Modules

For all cuda-capable discrete products with fans

return NVML_SUCCESS if speed has been adjusted

NVML_ERROR_UNINITIALIZED if the library has not been successfully

initialized NVML_ERROR_INVALID_ARGUMENT if device is invalid

NVML_ERROR_NOT_SUPPORTED if the device does not support this (doesn't have

fans) NVML_ERROR_UNKNOWN on any unexpected error

nvmlReturn_t nvmlDeviceGetFanControlPolicy_v2

(nvmlDevice_t device, unsigned int fan,

nvmlFanControlPolicy_t *policy)

Description

Gets current fan control policy.

For Maxwell or newer fully supported devices.

For all cuda-capable discrete products with fans

device The identifier of the target device policy Reference in which to return the fan

control policy

return NVML_SUCCESS if policy has been populated

NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

NVML_ERROR_INVALID_ARGUMENT if device is invalid or policy is null or the

fan given doesn't reference a fan that exists. NVML_ERROR_NOT_SUPPORTED if the

device is older than Maxwell NVML_ERROR_UNKNOWN on any unexpected error

nvmlReturn_t nvmlDeviceGetNumFans (nvmlDevice_t

device, unsigned int *numFans)

Parameters

device

The identifier of the target device

numFans

The number of fans

Returns

‣ NVML_SUCCESS if fan number query was successful

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or numFans is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have a fan

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‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the number of fans on the device.

For all discrete products with dedicated fans.

nvmlReturn_t nvmlDeviceGetTemperature

(nvmlDevice_t device, nvmlTemperatureSensors_t

sensorType, unsigned int *temp)

Description

Deprecated Use nvmlDeviceGetTemperatureV instead

nvmlReturn_t nvmlDeviceGetCoolerInfo (nvmlDevice_t

device, nvmlCoolerInfo_t *coolerInfo)

Parameters

device

The identifier of the target device

coolerInfo

Structure specifying the cooler's control signal characteristics (out) and the target that

cooler cools (out)

Returns

‣ NVML_SUCCESS If everything worked

‣ NVML_ERROR_UNINITIALIZED If the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT If device is invalid, signalType or target is

NULL

‣ NVML_ERROR_ARGUMENT_VERSION_MISMATCH If the provided version is

invalid/unsupported

‣ NVML_ERROR_NOT_SUPPORTED If the device does not support this feature

Description

Retrieves the cooler's information. Returns a cooler's control signal characteristics.

The possible types are restricted, Variable and Toggle. See nvmlCoolerControl_t for

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Modules

details on available signal types. Returns objects that cooler cools. Targets may be GPU,

Memory, Power Supply or All of these. See nvmlCoolerTarget_t for details on available

targets.

For Maxwell or newer fully supported devices.

For all discrete products with dedicated fans.

nvmlReturn_t nvmlDeviceGetTemperatureV

(nvmlDevice_t device, nvmlTemperature_t

*temperature)

Parameters

device

Target device identifier.

temperature

Structure specifying the sensor type (input) and retrieved temperature value (output).

Returns

‣ NVML_SUCCESS if temp has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, sensorType is invalid

or temp is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have the specified sensor

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the current temperature readings (in degrees C) for the given device.

For all products.

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nvmlReturn_t nvmlDeviceGetTemperatureThreshold

(nvmlDevice_t device, nvmlTemperatureThresholds_t

thresholdType, unsigned int *temp)

Parameters

device

The identifier of the target device

thresholdType

The type of threshold value queried

temp

Reference in which to return the temperature reading

Returns

‣ NVML_SUCCESS if temp has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, thresholdType is

invalid or temp is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not have a temperature

sensor or is unsupported

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the temperature threshold for the GPU with the specified threshold type in

degrees C.

For Kepler or newer fully supported devices.

See nvmlTemperatureThresholds_t for details on available temperature thresholds.

Note: This API is no longer the preferred interface for retrieving the

following temperature thresholds on Ada and later architectures:

NVML_TEMPERATURE_THRESHOLD_SHUTDOWN,

NVML_TEMPERATURE_THRESHOLD_SLOWDOWN,

NVML_TEMPERATURE_THRESHOLD_MEM_MAX and

NVML_TEMPERATURE_THRESHOLD_GPU_MAX.

Support for reading these temperature thresholds for Ada and later architectures would

be removed from this API in future releases. Please use nvmlDeviceGetFieldValues with

NVML_FI_DEV_TEMPERATURE_* fields to retrieve temperature thresholds on these

architectures.

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Modules

nvmlReturn_t nvmlDeviceGetMarginTemperature

(nvmlDevice_t device, nvmlMarginTemperature_t

*marginTempInfo)

Parameters

device

The identifier of the target device

marginTempInfo

Versioned structure in which to return the temperature reading

Returns

‣ NVML_SUCCESS if the margin temperature was retrieved successfully

‣ NVML_ERROR_NOT_SUPPORTED if request is not supported on the current

platform

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or temperature is

NULL

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_ARGUMENT_VERSION_MISMATCH if the right versioned

structure is not used

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the thermal margin temperature (distance to nearest slowdown threshold).

nvmlReturn_t nvmlDeviceGetThermalSettings

(nvmlDevice_t device, unsigned int sensorIndex,

nvmlGpuThermalSettings_t *pThermalSettings)

Parameters

device

The identifier of the target device

sensorIndex

The index of the thermal sensor

pThermalSettings

Reference in which to return the thermal sensor information

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Modules

Returns

‣ NVML_SUCCESS if pThermalSettings has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or pThermalSettings is

NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Used to execute a list of thermal system instructions.

nvmlReturn_t nvmlDeviceGetPerformanceState

(nvmlDevice_t device, nvmlPstates_t *pState)

Parameters

device

The identifier of the target device

pState

Reference in which to return the performance state reading

Returns

‣ NVML_SUCCESS if pState has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or pState is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves the current performance state for the device.

For Fermi or newer fully supported devices.

See nvmlPstates_t for details on allowed performance states.

157

Modules

nvmlReturn_t nvmlDeviceGetCurrentClocksEventReasons

(nvmlDevice_t device, unsigned long long

*clocksEventReasons)

Parameters

device

The identifier of the target device

clocksEventReasons

Reference in which to return bitmask of active clocks event reasons

Returns

‣ NVML_SUCCESS if clocksEventReasons has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or clocksEventReasons

is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves current clocks event reasons.

For all fully supported products.

More than one bit can be enabled at the same time. Multiple reasons can be affecting

clocks at once.

See also:

NvmlClocksEventReasons

nvmlDeviceGetSupportedClocksEventReasons

nvmlReturn_t

nvmlDeviceGetCurrentClocksThrottleReasons

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Modules

(nvmlDevice_t device, unsigned long long

*clocksThrottleReasons)

Description

Deprecated Use nvmlDeviceGetCurrentClocksEventReasons instead

nvmlReturn_t

nvmlDeviceGetSupportedClocksEventReasons

(nvmlDevice_t device, unsigned long long

*supportedClocksEventReasons)

Parameters

device

The identifier of the target device

supportedClocksEventReasons

Reference in which to return bitmask of supported clocks event reasons

Returns

‣ NVML_SUCCESS if supportedClocksEventReasons has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or

supportedClocksEventReasons is NULL

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves bitmask of supported clocks event reasons that can be returned by

nvmlDeviceGetCurrentClocksEventReasons

For all fully supported products.

This method is not supported in virtual machines running virtual GPU (vGPU).

See also:

NvmlClocksEventReasons

nvmlDeviceGetCurrentClocksEventReasons

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Modules

nvmlReturn_t

nvmlDeviceGetSupportedClocksThrottleReasons

(nvmlDevice_t device, unsigned long long

*supportedClocksThrottleReasons)

Description

Deprecated Use nvmlDeviceGetSupportedClocksEventReasons instead

nvmlReturn_t nvmlDeviceGetPowerState (nvmlDevice_t

device, nvmlPstates_t *pState)

Parameters

device

The identifier of the target device

pState

Reference in which to return the performance state reading

Returns

‣ NVML_SUCCESS if pState has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or pState is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Deprecated: Use nvmlDeviceGetPerformanceState. This function exposes an incorrect

generalization.

Retrieve the current performance state for the device.

For Fermi or newer fully supported devices.

See nvmlPstates_t for details on allowed performance states.

160

Modules

nvmlReturn_t nvmlDeviceGetDynamicPstatesInfo

(nvmlDevice_t device, nvmlGpuDynamicPstatesInfo_t

*pDynamicPstatesInfo)

Parameters

device

pDynamicPstatesInfo

Returns

‣ NVML_SUCCESS if pDynamicPstatesInfo has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or

pDynamicPstatesInfo is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve performance monitor samples from the associated subdevice.

nvmlReturn_t nvmlDeviceGetMemClkVfOffset

(nvmlDevice_t device, int *offset)

Parameters

device

The identifier of the target device

offset

The retrieved MemClk VF offset value

Returns

‣ NVML_SUCCESS if offset has been successfully queried

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or offset is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_UNKNOWN on any unexpected error

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Modules

Description

Retrieve the MemClk (Memory Clock) VF offset value.

nvmlReturn_t nvmlDeviceGetMinMaxClockOfPState

(nvmlDevice_t device, nvmlClockType_t type,

nvmlPstates_t pstate, unsigned int *minClockMHz,

unsigned int *maxClockMHz)

Parameters

device

The identifier of the target device

type

Clock domain

pstate

PState to query

minClockMHz

Reference in which to return min clock frequency

maxClockMHz

Reference in which to return max clock frequency

Returns

‣ NVML_SUCCESS if everything worked

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device, type or pstate are invalid or both

minClockMHz and maxClockMHz are NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

Description

Retrieve min and max clocks of some clock domain for a given PState

nvmlReturn_t

nvmlDeviceGetSupportedPerformanceStates

162

Modules

(nvmlDevice_t device, nvmlPstates_t *pstates, unsigned

int size)

Parameters

device

The identifier of the target device

pstates

Container to return the list of performance states supported by device

size

Size of the supplied pstates array in bytes

Returns

‣ NVML_SUCCESS if pstates array has been retrieved

‣ NVML_ERROR_INSUFFICIENT_SIZE if the the container supplied was not large

enough to hold the resulting list

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device or pstates is invalid

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support performance

state readings

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Get all supported Performance States (P-States) for the device.

The returned array would contain a contiguous list of valid P-States supported by the

device. If the number of supported P-States is fewer than the size of the array supplied

missing elements would contain NVML_PSTATE_UNKNOWN.

The number of elements in the returned list will never exceed

NVML_MAX_GPU_PERF_PSTATES.

nvmlReturn_t nvmlDeviceGetGpcClkMinMaxVfOffset

(nvmlDevice_t device, int *minOffset, int *maxOffset)

Parameters

device

The identifier of the target device

minOffset

The retrieved GPCCLK VF min offset value

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Modules

maxOffset

The retrieved GPCCLK VF max offset value

Returns

‣ NVML_SUCCESS if offset has been successfully queried

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or offset is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve the GPCCLK min max VF offset value.

nvmlReturn_t nvmlDeviceGetMemClkMinMaxVfOffset

(nvmlDevice_t device, int *minOffset, int *maxOffset)

Parameters

device

The identifier of the target device

minOffset

The retrieved MemClk VF min offset value

maxOffset

The retrieved MemClk VF max offset value

Returns

‣ NVML_SUCCESS if offset has been successfully queried

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid or offset is NULL

‣ NVML_ERROR_NOT_SUPPORTED if the device does not support this feature

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieve the MemClk (Memory Clock) min max VF offset value.

164

Modules

nvmlReturn_t nvmlDeviceGetClockOffsets (nvmlDevice_t

device, nvmlClockOffset_t *info)

Parameters

device

The identifier of the target device

info

Structure specifying the clock type (input) and the pstate (input) retrieved clock offset

value (output), min clock offset (output) and max clock offset (output)

Returns

‣ NVML_SUCCESS If everything worked

‣ NVML_ERROR_UNINITIALIZED If the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT If device, type or pstate are invalid or both

minClockOffsetMHz and maxClockOffsetMHz are NULL

‣ NVML_ERROR_ARGUMENT_VERSION_MISMATCH If the provided version is

invalid/unsupported

‣ NVML_ERROR_NOT_SUPPORTED If the device does not support this feature

Description

Retrieve min, max and current clock offset of some clock domain for a given PState

For Maxwell or newer fully supported devices.

Note: nvmlDeviceGetGpcClkVfOffset, nvmlDeviceGetMemClkVfOffset,

nvmlDeviceGetGpcClkMinMaxVfOffset and nvmlDeviceGetMemClkMinMaxVfOffset

will be deprecated in a future release. Use nvmlDeviceGetClockOffsets instead.

nvmlReturn_t nvmlDeviceSetClockOffsets (nvmlDevice_t

device, nvmlClockOffset_t *info)

Parameters

device

The identifier of the target device

info

Structure specifying the clock type (input), the pstate (input) and clock offset value

(input)

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Modules

Returns

‣ NVML_SUCCESS If everything worked

‣ NVML_ERROR_UNINITIALIZED If the library has not been successfully initialized

‣ NVML_ERROR_NO_PERMISSION If the user doesn't have permission to perform

this operation

‣ NVML_ERROR_INVALID_ARGUMENT If device, type or pstate are invalid or both

clockOffsetMHz is out of allowed range.

‣ NVML_ERROR_ARGUMENT_VERSION_MISMATCH If the provided version is

invalid/unsupported

‣ NVML_ERROR_NOT_SUPPORTED If the device does not support this feature

Description

Control current clock offset of some clock domain for a given PState

For Maxwell or newer fully supported devices.

Requires privileged user.

nvmlReturn_t nvmlDeviceGetPerformanceModes

(nvmlDevice_t device, nvmlDevicePerfModes_t

*perfModes)

Parameters

device

The identifier of the target device

perfModes

Reference in which to return the performance level string

Returns

‣ NVML_SUCCESS if perfModes has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or name is NULL

‣ NVML_ERROR_INSUFFICIENT_SIZE if length is too small

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves a performance mode string with all the performance modes defined for this

device along with their associated GPU Clock and Memory Clock values. Not all tokens

166

Modules

will be reported on all GPUs, and additional tokens may be added in the future. For

backwards compatibility we still provide nvclock and memclock; those are the same as

nvclockmin and memclockmin.

Note: These clock values take into account the offset set by clients through /ref

nvmlDeviceSetClockOffsets.

Maximum available Pstate (P15) shows the minimum performance level (0) and vice

versa.

Each performance modes are returned as a comma-separated list of "token=value" pairs.

Each set of performance mode tokens are separated by a ";". Valid tokens:

Token Value "perf" unsigned int - the Performance level "nvclock" unsigned int - the

GPU clocks (in MHz) for the perf level "nvclockmin" unsigned int - the GPU clocks

min (in MHz) for the perf level "nvclockmax" unsigned int - the GPU clocks max (in

MHz) for the perf level "nvclockeditable" unsigned int - if the GPU clock domain is

editable for the perf level "memclock" unsigned int - the memory clocks (in MHz) for

the perf level "memclockmin" unsigned int - the memory clocks min (in MHz) for the

perf level "memclockmax" unsigned int - the memory clocks max (in MHz) for the perf

level "memclockeditable" unsigned int - if the memory clock domain is editable for the

perf level "memtransferrate" unsigned int - the memory transfer rate (in MHz) for the

perf level "memtransferratemin" unsigned int - the memory transfer rate min (in MHz)

for the perf level "memtransferratemax" unsigned int - the memory transfer rate max (in

MHz) for the perf level "memtransferrateeditable" unsigned int - if the memory transfer

rate is editable for the perf level

Example:

perf=0, nvclock=324, nvclockmin=324, nvclockmax=324, nvclockeditable=0,

memclock=324, memclockmin=324, memclockmax=324, memclockeditable=0,

memtransferrate=648, memtransferratemin=648, memtransferratemax=648,

memtransferrateeditable=0 ; perf=1, nvclock=324, nvclockmin=324, nvclockmax=640,

nvclockeditable=0, memclock=810, memclockmin=810, memclockmax=810,

memclockeditable=0, memtransferrate=1620, memtransferrate=1620,

memtransferrate=1620, memtransferrateeditable=0 ;

nvmlReturn_t nvmlDeviceGetCurrentClockFreqs

(nvmlDevice_t device, nvmlDeviceCurrentClockFreqs_t

*currentClockFreqs)

Parameters

device

The identifier of the target device

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Modules

currentClockFreqs

Reference in which to return the performance level string

Returns

‣ NVML_SUCCESS if currentClockFreqs has been set

‣ NVML_ERROR_UNINITIALIZED if the library has not been successfully initialized

‣ NVML_ERROR_INVALID_ARGUMENT if device is invalid, or name is NULL

‣ NVML_ERROR_INSUFFICIENT_SIZE if length is too small

‣ NVML_ERROR_GPU_IS_LOST if the target GPU has fallen off the bus or is

otherwise inaccessible

‣ NVML_ERROR_UNKNOWN on any unexpected error

Description

Retrieves a string with the associated current GPU Clock and Memory Clock values.

Not all tokens will be reported on all GPUs, and additional tokens may be added in the

future.

Note: These clock values take into account the offset set by clients through /ref

nvmlDeviceSetClockOffsets.

Clock values are returned as a comma-separated list of "token=value" pairs. Valid tokens: