C Specification

Bits which may be set in VkMemoryType::propertyFlags, indicating properties of a memory heap, are:

typedef enum VkMemoryPropertyFlagBits {
    VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT = 0x00000001,
    VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT = 0x00000002,
    VK_MEMORY_PROPERTY_HOST_COHERENT_BIT = 0x00000004,
    VK_MEMORY_PROPERTY_HOST_CACHED_BIT = 0x00000008,
    VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT = 0x00000010,
} VkMemoryPropertyFlagBits;

Description

  • VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT bit indicates that memory allocated with this type is the most efficient for device access. This property will be set if and only if the memory type belongs to a heap with the VK_MEMORY_HEAP_DEVICE_LOCAL_BIT set.

  • VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT bit indicates that memory allocated with this type can be mapped for host access using vkMapMemory.

  • VK_MEMORY_PROPERTY_HOST_COHERENT_BIT bit indicates that the host cache management commands vkFlushMappedMemoryRanges and vkInvalidateMappedMemoryRanges are not needed to flush host writes to the device or make device writes visible to the host, respectively.

  • VK_MEMORY_PROPERTY_HOST_CACHED_BIT bit indicates that memory allocated with this type is cached on the host. Host memory accesses to uncached memory are slower than to cached memory, however uncached memory is always host coherent.

  • VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT bit indicates that the memory type only allows device access to the memory. Memory types must not have both VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT and VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT set. Additionally, the object’s backing memory may be provided by the implementation lazily as specified in Lazily Allocated Memory.

See Also

Document Notes

For more information, see the Vulkan Specification at URL

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

Copyright (c) 2014-2017 Khronos Group. This work is licensed under a Creative Commons Attribution 4.0 International License.