VulkanHub

VK_EXT_zero_initialize_device_memory

Other Extension Metadata

Last Modified Date

2025-04-09

Interactions and External Dependencies
IP Status

No known IP claims.

Contributors
  • Hans-Kristian Arntzen, VALVE
  • Mike Blumenkrantz, VALVE
  • Tobias Hector, AMD
  • Faith Ekstrand, Collabora
  • Ricardo Garcia, Igalia
  • Jan-Harald Fredriksen, ARM
  • Spencer Fricke, LunarG

Description

By default, Vulkan provides no guarantees that device memory allocated through vkAllocateMemory is cleared to zero. This means that applications wanting resources to be zero-initialized must execute a command such as vkCmdFillBuffer or vkCmdClearColorImage on the device to ensure a deterministic result. This can be wasteful if the underlying platform either:

  • Already performs that zero clear anyway, due to e.g. security concerns.
  • Can be performed more efficiently in implementation, by e.g. clearing pages to zero in the background after device memory is freed.

This extension also has uses in API layering and porting efforts, where zero memory behavior may be more strict than Vulkan. Different OS platforms also have wildly different behaviors here, which leads to implementations needing to apply workarounds to paper over these issues in the wild. If an extension exists to make allocation behavior explicit, we hopefully achieve a more robust ecosystem for Vulkan.

New Structures

New Enum Constants

  • VK_EXT_ZERO_INITIALIZE_DEVICE_MEMORY_EXTENSION_NAME
  • VK_EXT_ZERO_INITIALIZE_DEVICE_MEMORY_SPEC_VERSION
  • Extending VkImageLayout:
    • VK_IMAGE_LAYOUT_ZERO_INITIALIZED_EXT
  • Extending VkMemoryAllocateFlagBits:
    • VK_MEMORY_ALLOCATE_ZERO_INITIALIZE_BIT_EXT
  • Extending VkStructureType:
    • VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_ZERO_INITIALIZE_DEVICE_MEMORY_FEATURES_EXT

Version History

  • Revision 1, 2025-03-10 (Mike Blumenkrantz)
    • Initial version