Need to cudaSetDevice again after cudaDeviceReset?

Accelerated Computing CUDA CUDA Programming and Performance
1

need to cudaSetDevice again after cudaDeviceReset ?
thanks

2

It may be necessary. I would certainly expect it to be necessary if the device you intend to use is other than device 0, the default.

3

thanks! how about always using the only device 0 ? not necessary but better&safe to call cudaSetDevice(0) again?

4

I pretty much never use cudaDeviceReset. I think it is a bad idea. So I don’t really have lots of detailed recommendations for its use. I don’t think it ever needs to be used. I wouldn’t use it and I wouldn’t recommend that it be used.

When I only have a single device in view, I don’t bother ever calling cudaSetDevice(0), either. That is an API default.

5

it seems it will free more gpu memory after cudaDeviceReset than not call it after free all cuda objects.

6

so what’s the best way to switch device when multi-devices. while running. thanks!