Data Type

Integer

Default Value

GPU threads are bound to groups of CPU cores in order.
For example, a system having 32 CPU cores and 4 GPUs, the GPU threads would be bound as follows:
GPU CPUs used
1 1 - 8
2 9 - 16
3 17 - 24
4 25 - 32

Description

This parameter binds the thread controlling a GPU to run on a specified range of CPU cores. The bus where each GPU is interfaced will be controlled by a single CPU Processor. Binding the thread controlling that GPU to the cores in the processor where it is interfaced can reduce memory traffic.

The form of this command is: 

GPUCPU=GPU#,CPU1:CPU2

where GPU# is the GPU number (starting at 1) and CPU1:CPU2 is the range of CPU cores (starting at 1). For example, to bind GPU 2 to CPU cores 9 through 16 you would enter 

GPUCPU=2,9:16

This command should be placed in the license file between the FMSSET and RETURN lines.

You should not include hyperthreads when making these bindings. A list of hyperthreads is given on the CPU WEB page.

To determine what GPUs are attached to what processors and if binding the threads would make any difference, run the CPU-GPU memory tests described on CGTEST.