// Copyright (c) 2014-2019 Khronos Group. This work is licensed under a
// Creative Commons Attribution 4.0 International License; see
// http://creativecommons.org/licenses/by/4.0/
// This section is included inside the Pipelines chapter (pipelines.txt)
[[pipelines-creation-feedback]]
== Pipeline Creation Feedback
[open,refpage='VkPipelineCreationFeedbackCreateInfoEXT',desc='Request for feedback about the creation of a pipeline',type='structs',xrefs='VkGraphicsPipelineCreateInfo VkComputePipelineCreateInfo VkRayTracingPipelineCreateInfoNV VkPipelineCreationFeedbackEXT']
--
Feedback about the creation of a particular pipeline object can: be obtained
by including a sname:VkPipelineCreationFeedbackCreateInfoEXT structure in
the pNext chain of slink:VkGraphicsPipelineCreateInfo,
ifdef::VK_NV_ray_tracing[]
slink:VkRayTracingPipelineCreateInfoNV,
endif::VK_NV_ray_tracing[]
or slink:VkComputePipelineCreateInfo.
The sname:VkPipelineCreationFeedbackCreateInfoEXT structure is defined as:
[open,refpage='VkPipelineCreationFeedbackEXT',desc='Feedback about the creation of a pipeline or pipeline stage',type='structs',xrefs='VkPipelineCreationFeedbackCreateInfoEXT VkPipelineCreationFeedbackFlagBitsEXT']
--
The sname:VkPipelineCreationFeedbackEXT structure is defined as:
pname:basePipelineHandle or pname:basePipelineIndex member of the
stext:Vk*PipelineCreateInfo structure was used to accelerate the
creation of the pipeline.
+
An implementation should: set the
ename:VK_PIPELINE_CREATION_FEEDBACK_BASE_PIPELINE_ACCELERATION_BIT_EXT bit
if it was able to avoid a significant amount of work by using the base
pipeline.
+
[NOTE]
.Note
====
While "significant amount of work" is subjective, implementations are
encouraged to provide a meaningful signal to applications using this bit.
For example, a 1% reduction in duration may not warrant setting this bit,
while a 50% reduction would.
====
--
[open,refpage='VkPipelineCreationFeedbackFlagsEXT',desc='Bitmask of VkPipelineCreationFeedbackFlagBitsEXT',type='flags',xrefs='VkPipelineCreationFeedbackEXT VkPipelineCreationFeedbackFlagBitsEXT']