User`s guide

9 GPU Computing

9-18

Identify and Select a GPU Device

If you have only one GPU in your computer, that GPU is the default. If you have more

than one GPU device in your computer, you can use the following functions to identify

and select which device you want to use:

Function Description

gpuDeviceCount The number of GPU devices in your computer

gpuDevice Select which device to use, or see which device is selected

and view its properties

Example: Select a GPU

This example shows how to identify and select a GPU for your computations.

Determine how many GPU devices are in your computer:

gpuDeviceCount

With two devices, the first is the default. You can examine its properties to

determine if that is the one you want to use:

d = gpuDevice

d =

CUDADevice with properties:

Name: 'Tesla K20c'

Index: 1

ComputeCapability: '3.5'

SupportsDouble: 1

DriverVersion: 5.5000

ToolkitVersion: 5.5000

MaxThreadsPerBlock: 1024

MaxShmemPerBlock: 49152

MaxThreadBlockSize: [1024 1024 64]

MaxGridSize: [2.1475e+09 65535 65535]

SIMDWidth: 32

TotalMemory: 5.0327e+09