To query the number of additional threads that can usefully be joined to a deferred operation, call:
// Provided by VK_KHR_deferred_host_operations uint32_t vkGetDeferredOperationMaxConcurrencyKHR( VkDevice device, VkDeferredOperationKHR operation);
deviceis the device which owns
operationis the deferred operation to be queried.
The returned value is the maximum number of threads that can usefully
execute a deferred operation concurrently, reported for the state of the
deferred operation at the point this command is called.
This value is intended to be used to better schedule work onto available
Applications can join any number of threads to the deferred operation and
expect it to eventually complete, though excessive joins may return
VK_THREAD_DONE_KHR immediately, performing no useful work.
operation is complete,
vkGetDeferredOperationMaxConcurrencyKHR returns zero.
operation is currently joined to any threads, the value returned by
this command may immediately be out of date.
operation is pending, implementations must not return zero unless
at least one thread is currently executing vkDeferredOperationJoinKHR
If there are such threads, the implementation should return an estimate of
the number of additional threads which it could profitably use.
Implementations may return 232-1 to indicate that the maximum concurrency is unknown and cannot be easily derived. Implementations may return values larger than the maximum concurrency available on the host CPU. In these situations, an application should clamp the return value rather than oversubscribing the machine.
The recommended usage pattern for applications is to query this value once,
after deferral, and schedule no more than the specified number of threads to
join the operation.
Each time a joined thread receives
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.