ID3D12CommandQueue::ExecuteCommandLists Method

Submits an array of command lists for execution.

Syntax

public:
void ExecuteCommandLists(
         UINT Count,
         const ID3D12CommandList *ppCommandLists
)

Parameters

Count
Type: UINT

[in] The number of command lists to be executed.

ppCommandLists
Type: ID3D12CommandList *

[in] The array of ID3D12CommandList command lists to be executed.

Return value

Type: void

Returns nothing.

Remarks

It is the calling application’s responsibility to ensure that the graphics processing unit (GPU) is not currently reading the any of the submitted command lists from a previous execution.

Applications are encouraged to batch together command list executions to reduce fixed costs associated with submitted commands to the GPU.

Asynchronous Execution

It is permitted (as an Xbox extension) to execute a command list before it has been closed, and continue recording commands to the list. When a command list executed on a queue has not yet been closed, all subsequent work issued to that queue will back up and not be submitted to the GPU until the command list Close is called. Asynchronous execution support includes graphics (direct), compute, and dma command lists.

Use of asynchronous command list execution has the following restrictions:

An open command list executed asynchronously on a queue cannot be executed on the same or any other queue before the list is closed. After the close it may be executed repeatedly in the traditional fashion.
The thread responsible for completing an asynchronously executed command list must not use the queue on which that list has been executed until the list has been closed. Doing so may lead to deadlocks.
No protection is provided for one thread executing a command list at the same time another thread is recording to the list. It is the responsibility of the title to ensure thread safety.
All asynchronously executed command lists must be closed before a Suspend call.
Currently, PIX capture support requires that all asynchronously executed command lists be closed before the Present call.
It is recommended to avoid failure conditions of any kind in command list recording after executing a list. Failure post-execution will yield a partially executed list that cannot be completed. As it is not possible to pinpoint out-of-memory or validation failure locations, what has actually been submitted to the GPU is uncertain, and referenced resources will be effectively left in an indeterminate state (barriers, for example).

After execution, commands recorded to a command list will be automatically submitted to the GPU upon completion of each segment (the D3D12XBOX_COMMAND_LIST_FLAG_DISABLE_AUTOMATIC_KICKOFFS - see D3D12XBOX_COMMAND_LIST_FLAGS - flag may be specified at command list creation to disable such automatic submission). To initiate immediate submission of recorded commands (useful for intra-command list synchronization), one of the command list methods:

may be called to force completion of the current segment and submit it for processing. Close will submit the final command list segment, as well as any other work pending on the execution queue.

Requirements

Header: Declared in d3d12_x.h.

Library: Use d3d12_x.lib.