Essentials

functional(show_reason=false)

Check if the package has been configured successfully and is ready to use.

This call is intended for packages that support conditionally using an available GPU. If you fail to check whether CUDA is functional, actual use of functionality might warn and error.

has_cuda()::Bool

Check whether the local system provides an installation of the CUDA driver and runtime. Use this function if your code loads packages that require CUDA.jl. ```

has_cuda_gpu()::Bool

Check whether the local system provides an installation of the CUDA driver and runtime, and if it contains a CUDA-capable GPU. See has_cuda for more details.

Note that this function initializes the CUDA API in order to check for the number of GPUs.

context(ptr)

Identify the context a CUDA memory buffer was allocated in.

context()::CuContext

Get or create a CUDA context for the current thread (as opposed to current_context which may return nothing if there is no context bound to the current thread).

context!(ctx::CuContext)
context!(ctx::CuContext) do ... end

Bind the current host thread to the context ctx. Returns the previously-bound context. If used with do-block syntax, the change is only temporary.

Note that the contexts used with this call should be previously acquired by calling context, and not arbitrary contexts created by calling the CuContext constructor.

device(::CuContext)

Returns the device for a context.

device(ptr)

Identify the device a CUDA memory buffer was allocated on.

device()::CuDevice

Get the CUDA device for the current thread, similar to how context() works compared to current_context().

device!(dev::Integer)
device!(dev::CuDevice)
device!(dev) do ... end

Sets dev as the current active device for the calling host thread. Devices can be specified by integer id, or as a CuDevice (slightly faster). Both functions can be used with do-block syntax, in which case the device is only changed temporarily, without changing the default device used to initialize new threads or tasks.

Calling this function at the start of a session will make sure CUDA is initialized (i.e., a primary context will be created and activated).

device_reset!(dev::CuDevice=device())

Reset the CUDA state associated with a device. This call with release the underlying context, at which point any objects allocated in that context will be invalidated.

stream()

Get the CUDA stream that should be used as the default one for the currently executing task.

stream!(::CuStream)
stream!(::CuStream) do ... end

Change the default CUDA stream for the currently executing task, temporarily if using the do-block version of this function.