C Specification

The VkMemoryDedicatedRequirements structure is defined as:

// Provided by VK_VERSION_1_1
typedef struct VkMemoryDedicatedRequirements {
    VkStructureType    sType;
    void*              pNext;
    VkBool32           prefersDedicatedAllocation;
    VkBool32           requiresDedicatedAllocation;
} VkMemoryDedicatedRequirements;

or the equivalent

// Provided by VK_KHR_dedicated_allocation
typedef VkMemoryDedicatedRequirements VkMemoryDedicatedRequirementsKHR;

Members

  • sType is the type of this structure.

  • pNext is NULL or a pointer to a structure extending this structure.

  • prefersDedicatedAllocation specifies that the implementation would prefer a dedicated allocation for this resource. The application is still free to suballocate the resource but it may get better performance if a dedicated allocation is used.

  • requiresDedicatedAllocation specifies that a dedicated allocation is required for this resource.

Description

To determine the dedicated allocation requirements of a buffer or image resource, add a VkMemoryDedicatedRequirements structure to the pNext chain of the VkMemoryRequirements2 structure passed as the pMemoryRequirements parameter of vkGetBufferMemoryRequirements2 or vkGetImageMemoryRequirements2, respectively.

Constraints on the values returned for buffer resources are:

  • requiresDedicatedAllocation may be VK_TRUE if the pNext chain of VkBufferCreateInfo for the call to vkCreateBuffer used to create the buffer being queried included a VkExternalMemoryBufferCreateInfo structure, and any of the handle types specified in VkExternalMemoryBufferCreateInfo::handleTypes requires dedicated allocation, as reported by vkGetPhysicalDeviceExternalBufferProperties in VkExternalBufferProperties::externalMemoryProperties.externalMemoryFeatures. Otherwise, requiresDedicatedAllocation will be VK_FALSE.

  • When the implementation sets requiresDedicatedAllocation to VK_TRUE, it must also set prefersDedicatedAllocation to VK_TRUE.

  • If VK_BUFFER_CREATE_SPARSE_BINDING_BIT was set in VkBufferCreateInfo::flags when buffer was created, then both prefersDedicatedAllocation and requiresDedicatedAllocation will be VK_FALSE.

Constraints on the values returned for image resources are:

Valid Usage (Implicit)
  • VUID-VkMemoryDedicatedRequirements-sType-sType
    sType must be VK_STRUCTURE_TYPE_MEMORY_DEDICATED_REQUIREMENTS

See Also

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 2014-2021 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0