Dolphin CudaBase

CudaBase

class dolphin.CudaBase

Bases: object

This class is mainly used to access device information, such as maximum number of threads per block, size of grid etc… This is a base class used by many other classes. It has a lot of class attributes in order not to load the same things again and again in order to speed up execution.

device: pycuda._driver.Device

Used device

max_threads_per_block: int

Maximum number of threads per blocks. Usually, it is 1024

max_grid_dim_x: int

Maximum number of blocks per grid x on dim

max_grid_dim_y: int

Maximum number of blocks per grid y on dim

max_grid_dim_z: int

Maximum number of blocks per grid z on dim

warp_size: int

Warp size

multiprocessor_count: int

Number of MP

threads_blocks_per_mp: int

Number of threads per MP

static GET_BLOCK_GRID_1D(n: int) → Tuple[Tuple[int, int, int], Tuple[int, int]]

In ordert to perform memory coalescing on 1D iterations, we need to efficiently compute the block & grid sizes.

Parameters:

n (int) – Number of elements to process

Returns:

block, grid

Return type:

Tuple[Tuple[int, int, int], Tuple[int, int]]

static GET_BLOCK_X_Y(Z: int) → Tuple[int, int, int]

Get the block size for a given Z. The block size is calculated using the following formula: (max(ceil(sqrt(MAX_THREADS_PER_BLOCKS/Z)),1), max(ceil(sqrt(MAX_THREADS_PER_BLOCKS/Z)),1), Z)

It is useful to quickly compute the block size that suits self._max_threads_per_block for a given Z which can be channels, depth, batch size, etc.

Parameters:

Z (int) – Size of the third dimension

Returns:

Optimal block size that ensure block[0]*block[1]*block[2] <= self._max_threads_per_block

Return type:

tuple

static GET_GRID_SIZE(size: tuple, block: tuple) → Tuple[int, int]

Get the grid size for a given size and block size. The grid size is calculated using the following formula: (max(ceil(sqrt(size/block[0])),1), max(ceil(sqrt(size/block[1])),1))

This function should be used when the width and height of the image are the same or can be swapped.

Parameters:

• size (tuple) – Total size of data

• block (tuple) – Current value of the block size

Returns:

Grid size

Return type:

tuple

static GET_GRID_SIZE_HW(size: tuple, block: tuple) → Tuple[int, int]

Get the grid size for a given size and block size. The grid size is calculated using the following formula: (max(ceil(sqrt(size[0]/block[0])),1), max(ceil(sqrt(size[1]/block[1])),1))

This function should be used when the width and height of the image are different and matter.

Parameters:

• size (tuple) – Height and width of the image

• block (tuple) – Current value of the block size

Returns:

Grid size

Return type:

tuple