VK_VALVE_buffer_device_address_allocation_alignment

Other Extension Metadata

Last Modified Date

2026-08-26

IP Status

No known IP claims.

Contributors

• Hans-Kristian Arntzen, Valve
• Connor Abbott, Valve

Description

This extension allows applications to specify the alignment of any buffer device address allocation, beyond the current specification requirements which only requires that the memory has enough alignment to satisfy any alignment request the implementation may require on its own.

When layering some other APIs, e.g. D3D12, applications are sometimes able to rely on the allocated buffer device address being aligned to a potentially larger alignment than what the implementation would normally allocate for. Some applications rely on this implementation detail and will behave in unexpected ways if tighter alignments are used. vkAllocateMemory as well as sparse buffer creation is affected by this and this extension adds extra requirements on the implementation when requested by application.

New Structures

• Extending VkBufferCreateInfo, VkMemoryAllocateInfo:
  • VkBufferDeviceAddressAlignmentAllocateInfoVALVE
• Extending VkPhysicalDeviceFeatures2, VkDeviceCreateInfo:
  • VkPhysicalDeviceBufferDeviceAddressAllocationAlignmentFeaturesVALVE
• Extending VkPhysicalDeviceProperties2:
  • VkPhysicalDeviceBufferDeviceAddressAllocationAlignmentPropertiesVALVE

New Enum Constants

• VK_VALVE_BUFFER_DEVICE_ADDRESS_ALLOCATION_ALIGNMENT_EXTENSION_NAME
• VK_VALVE_BUFFER_DEVICE_ADDRESS_ALLOCATION_ALIGNMENT_SPEC_VERSION
• Extending VkStructureType:
  • VK_STRUCTURE_TYPE_BUFFER_DEVICE_ADDRESS_ALIGNMENT_ALLOCATE_INFO_VALVE
  • VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_BUFFER_DEVICE_ADDRESS_ALLOCATION_ALIGNMENT_FEATURES_VALVE
  • VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_BUFFER_DEVICE_ADDRESS_ALLOCATION_ALIGNMENT_PROPERTIES_VALVE

Version History

• Revision 1, 2026-08-26 (Hans-Kristian Arntzen)
  • Initial specification