C Specification

To retrieve a list of the device groups present in the system, call:

// Provided by VK_VERSION_1_1
VkResult vkEnumeratePhysicalDeviceGroups(
    VkInstance                                  instance,
    uint32_t*                                   pPhysicalDeviceGroupCount,
    VkPhysicalDeviceGroupProperties*            pPhysicalDeviceGroupProperties);

or the equivalent command

// Provided by VK_KHR_device_group_creation
VkResult vkEnumeratePhysicalDeviceGroupsKHR(
    VkInstance                                  instance,
    uint32_t*                                   pPhysicalDeviceGroupCount,
    VkPhysicalDeviceGroupProperties*            pPhysicalDeviceGroupProperties);

Parameters

  • instance is a handle to a Vulkan instance previously created with vkCreateInstance.

  • pPhysicalDeviceGroupCount is a pointer to an integer related to the number of device groups available or queried, as described below.

  • pPhysicalDeviceGroupProperties is either NULL or a pointer to an array of VkPhysicalDeviceGroupProperties structures.

Description

If pPhysicalDeviceGroupProperties is NULL, then the number of device groups available is returned in pPhysicalDeviceGroupCount. Otherwise, pPhysicalDeviceGroupCount must point to a variable set by the user to the number of elements in the pPhysicalDeviceGroupProperties array, and on return the variable is overwritten with the number of structures actually written to pPhysicalDeviceGroupProperties. If pPhysicalDeviceGroupCount is less than the number of device groups available, at most pPhysicalDeviceGroupCount structures will be written, and VK_INCOMPLETE will be returned instead of VK_SUCCESS, to indicate that not all the available device groups were returned.

Every physical device must be in exactly one device group.

Valid Usage (Implicit)

  • VUID-vkEnumeratePhysicalDeviceGroups-instance-parameter
    instance must be a valid VkInstance handle

  • VUID-vkEnumeratePhysicalDeviceGroups-pPhysicalDeviceGroupCount-parameter
    pPhysicalDeviceGroupCount must be a valid pointer to a uint32_t value

  • VUID-vkEnumeratePhysicalDeviceGroups-pPhysicalDeviceGroupProperties-parameter
    If the value referenced by pPhysicalDeviceGroupCount is not 0, and pPhysicalDeviceGroupProperties is not NULL, pPhysicalDeviceGroupProperties must be a valid pointer to an array of pPhysicalDeviceGroupCount VkPhysicalDeviceGroupProperties structures

Return Codes
On success, this command returns

  • VK_SUCCESS

  • VK_INCOMPLETE

On failure, this command returns

  • VK_ERROR_OUT_OF_HOST_MEMORY

  • VK_ERROR_OUT_OF_DEVICE_MEMORY

  • VK_ERROR_INITIALIZATION_FAILED

See Also

VK_VERSION_1_1, VkInstance, VkPhysicalDeviceGroupProperties

Document Notes

For more information, see the Vulkan Specification

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.

Copyright

Copyright 2014-2024 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0