DESCRIPTOR_SET_LAYOUT_CREATE_HOST_ONLY_POOL_BIT_VALVE specifies that descriptor sets using this layout must be allocated from a descriptor pool created with the DESCRIPTOR_POOL_CREATE_HOST_ONLY_BIT_VALVE bit set. Descriptor set layouts created with this bit have no expressable limit for maximum number of descriptors per-stage. Host descriptor sets are limited only by available host memory, but may be limited for implementation specific reasons. Implementations may limit the number of supported descriptors to UpdateAfterBind limits or non-UpdateAfterBind limits, whichever is larger.

DESCRIPTOR_SET_LAYOUT_CREATE_PUSH_DESCRIPTOR_BIT_KHR specifies that descriptor sets must not be allocated using this layout, and descriptors are instead pushed by cmdPushDescriptorSetKHR.

DESCRIPTOR_SET_LAYOUT_CREATE_UPDATE_AFTER_BIND_POOL_BIT specifies that descriptor sets using this layout must be allocated from a descriptor pool created with the DESCRIPTOR_POOL_CREATE_UPDATE_AFTER_BIND_BIT bit set. Descriptor set layouts created with this bit set have alternate limits for the maximum number of descriptors per-stage and per-pipeline layout. The non-UpdateAfterBind limits only count descriptors in sets created without this flag. The UpdateAfterBind limits count all descriptors, but the limits may be higher than the non-UpdateAfterBind limits.