Registered Extension Number

175

Revision

2

Extension and Version Dependencies

  • Requires Vulkan 1.0

Other Extension Metadata

Last Modified Date

2017-10-06

IP Status

No known IP claims.

Contributors
  • Andres Rodriguez, Valve

  • Pierre-Loup Griffais, Valve

  • Dan Ginsburg, Valve

  • Mitch Singer, AMD

Description

In Vulkan, users can specify device-scope queue priorities. In some cases it may be useful to extend this concept to a system-wide scope. This extension provides a mechanism for caller’s to set their system-wide priority. The default queue priority is VK_QUEUE_GLOBAL_PRIORITY_MEDIUM_EXT.

The driver implementation will attempt to skew hardware resource allocation in favour of the higher-priority task. Therefore, higher-priority work may retain similar latency and throughput characteristics even if the system is congested with lower priority work.

The global priority level of a queue shall take precedence over the per-process queue priority (VkDeviceQueueCreateInfo::pQueuePriorities).

Abuse of this feature may result in starving the rest of the system from hardware resources. Therefore, the driver implementation may deny requests to acquire a priority above the default priority (VK_QUEUE_GLOBAL_PRIORITY_MEDIUM_EXT) if the caller does not have sufficient privileges. In this scenario VK_ERROR_NOT_PERMITTED_EXT is returned.

The driver implementation may fail the queue allocation request if resources required to complete the operation have been exhausted (either by the same process or a different process). In this scenario VK_ERROR_INITIALIZATION_FAILED is returned.

New Object Types

None.

New Enum Constants

  • Extending VkStructureType:

    • VK_STRUCTURE_TYPE_DEVICE_QUEUE_GLOBAL_PRIORITY_CREATE_INFO_EXT

  • Extending VkResult:

    • VK_ERROR_NOT_PERMITTED_EXT

New Functions

None.

Issues

None.

Version History

  • Revision 2, 2017-11-03 (Andres Rodriguez)

    • Fixed VkQueueGlobalPriorityEXT missing _EXT suffix

  • Revision 1, 2017-10-06 (Andres Rodriguez)

    • First version.

See Also

Document Notes

For more information, see the Vulkan Specification

This page is a generated document. Fixes and changes should be made to the generator scripts, not directly.

Copyright (c) 2014-2020 Khronos Group. This work is licensed under a Creative Commons Attribution 4.0 International License.