C Specification

Bits which may be set in vkGetDeviceGroupPeerMemoryFeatures::pPeerMemoryFeatures, indicating supported peer memory features, are:

// Provided by VK_VERSION_1_1
typedef enum VkPeerMemoryFeatureFlagBits {
    VK_PEER_MEMORY_FEATURE_COPY_SRC_BIT = 0x00000001,
    VK_PEER_MEMORY_FEATURE_COPY_DST_BIT = 0x00000002,
    VK_PEER_MEMORY_FEATURE_GENERIC_SRC_BIT = 0x00000004,
    VK_PEER_MEMORY_FEATURE_GENERIC_DST_BIT = 0x00000008,
  // Provided by VK_KHR_device_group
    VK_PEER_MEMORY_FEATURE_COPY_SRC_BIT_KHR = VK_PEER_MEMORY_FEATURE_COPY_SRC_BIT,
  // Provided by VK_KHR_device_group
    VK_PEER_MEMORY_FEATURE_COPY_DST_BIT_KHR = VK_PEER_MEMORY_FEATURE_COPY_DST_BIT,
  // Provided by VK_KHR_device_group
    VK_PEER_MEMORY_FEATURE_GENERIC_SRC_BIT_KHR = VK_PEER_MEMORY_FEATURE_GENERIC_SRC_BIT,
  // Provided by VK_KHR_device_group
    VK_PEER_MEMORY_FEATURE_GENERIC_DST_BIT_KHR = VK_PEER_MEMORY_FEATURE_GENERIC_DST_BIT,
} VkPeerMemoryFeatureFlagBits;

or the equivalent

// Provided by VK_KHR_device_group
typedef VkPeerMemoryFeatureFlagBits VkPeerMemoryFeatureFlagBitsKHR;

Description

  • VK_PEER_MEMORY_FEATURE_COPY_SRC_BIT specifies that the memory can be accessed as the source of any vkCmdCopy* command.

  • VK_PEER_MEMORY_FEATURE_COPY_DST_BIT specifies that the memory can be accessed as the destination of any vkCmdCopy* command.

  • VK_PEER_MEMORY_FEATURE_GENERIC_SRC_BIT specifies that the memory can be read as any memory access type.

  • VK_PEER_MEMORY_FEATURE_GENERIC_DST_BIT specifies that the memory can be written as any memory access type. Shader atomics are considered to be writes.

Note

The peer memory features of a memory heap also apply to any accesses that may be performed during image layout transitions.

VK_PEER_MEMORY_FEATURE_COPY_DST_BIT must be supported for all host local heaps and for at least one device-local memory heap.

If a device does not support a peer memory feature, it is still valid to use a resource that includes both local and peer memory bindings with the corresponding access type as long as only the local bindings are actually accessed. For example, an application doing split-frame rendering would use framebuffer attachments that include both local and peer memory bindings, but would scissor the rendering to only update local memory.

See Also

VK_VERSION_1_1, VkPeerMemoryFeatureFlags

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