pyarrow.cuda.CudaBuffer

class pyarrow.cuda.CudaBuffer

Bases: pyarrow.lib.Buffer

An Arrow buffer with data located in a GPU device.

To create a CudaBuffer instance, use Context.device_buffer().

The memory allocated in a CudaBuffer is freed when the buffer object is deleted.

__init__(*args, **kwargs)

Initialize self. See help(type(self)) for accurate signature.

Methods

__init__(*args, **kwargs)	Initialize self.
copy_from_device	Copy data from device to device.
copy_from_host	Copy data from host to device.
copy_to_host	Copy memory from GPU device to CPU host
equals(self, Buffer other)	Determine if two buffers contain exactly the same data.
export_for_ipc	Expose this device buffer as IPC memory which can be used in other processes.
from_buffer	Convert back generic buffer into CudaBuffer
from_numba	Create a CudaBuffer view from numba MemoryPointer instance.
hex(self)	Compute hexadecimal representation of the buffer.
slice	Return slice of device buffer
to_numba	Return numba memory pointer of CudaBuffer instance.
to_pybytes	Return device buffer content as Python bytes.

Attributes

address	The buffer’s address, as an integer.
context	Returns the CUDA driver context of this buffer.
is_cpu	Whether the buffer is CPU-accessible.
is_mutable	Whether the buffer is mutable.
parent
size	The buffer size in bytes.

address

The buffer’s address, as an integer.

The returned address may point to CPU or device memory. Use is_cpu() to disambiguate.

context

Returns the CUDA driver context of this buffer.

copy_from_device()

Copy data from device to device.

Parameters

• buf (CudaBuffer) – Specify source device buffer.

• position (int) – Specify the starting position of the copy in device buffer. Default: 0.

• nbytes (int) – Specify the number of bytes to copy. Default: -1 (all from source until device buffer, starting from position, is full)

Returns

nbytes (int) – Number of bytes copied.

copy_from_host()

Copy data from host to device.

The device buffer must be pre-allocated.

Parameters

• data ({Buffer, array-like}) – Specify data in host. It can be array-like that is valid argument to py_buffer

• position (int) – Specify the starting position of the copy in device buffer. Default: 0.

• nbytes (int) – Specify the number of bytes to copy. Default: -1 (all from source until device buffer, starting from position, is full)

Returns

nbytes (int) – Number of bytes copied.

copy_to_host()

Copy memory from GPU device to CPU host

Caller is responsible for ensuring that all tasks affecting the memory are finished. Use

<CudaBuffer instance>.context.synchronize()

when needed.

Parameters

• position (int) – Specify the starting position of the source data in GPU device buffer. Default: 0.

• nbytes (int) – Specify the number of bytes to copy. Default: -1 (all from the position until host buffer is full).

• buf (Buffer) – Specify a pre-allocated output buffer in host. Default: None (allocate new output buffer).

• memory_pool (MemoryPool) –

• resizable (bool) – Specify extra arguments to allocate_buffer. Used only when buf is None.

Returns

buf (Buffer) – Output buffer in host.

equals(self, Buffer other)

Determine if two buffers contain exactly the same data.

Parameters

other (Buffer) –

Returns

are_equal (True if buffer contents and size are equal)

export_for_ipc()

Expose this device buffer as IPC memory which can be used in other processes.

After calling this function, this device memory will not be freed when the CudaBuffer is destructed.

Returns

ipc_handle (IpcMemHandle) – The exported IPC handle

static from_buffer()

Convert back generic buffer into CudaBuffer

Parameters

buf (Buffer) – Specify buffer containing CudaBuffer

Returns

dbuf (CudaBuffer) – Resulting device buffer.

static from_numba()

Create a CudaBuffer view from numba MemoryPointer instance.

Parameters

mem (numba.cuda.cudadrv.driver.MemoryPointer) –

Returns

cbuf (CudaBuffer) – Device buffer as a view of numba MemoryPointer.

hex(self)

Compute hexadecimal representation of the buffer.

Returns

bytes

is_cpu

Whether the buffer is CPU-accessible.

is_mutable

Whether the buffer is mutable.

parent

size

The buffer size in bytes.

slice()

Return slice of device buffer

Parameters

• offset (int, default 0) – Specify offset from the start of device buffer to slice

• length (int, default None) – Specify the length of slice (default is until end of device buffer starting from offset). If the length is larger than the data available, the returned slice will have a size of the available data starting from the offset.

Returns

sliced (CudaBuffer) – Zero-copy slice of device buffer.

to_numba()

Return numba memory pointer of CudaBuffer instance.

to_pybytes()

Return device buffer content as Python bytes.