UnifiedMemoryStreams example get stuck

Greetings, I am running the ./UnifiedMemoryStreams example given by CUDA 7.0 and receive the following message

GPU Device 0: “GeForce GTX 980” with compute capability 5.2

and later nothing … e.g. it get stuck.

I have writen a small test:


int *ret;
cudaStream_t stream = NULL;
if(!stream) {
	printf("failed to alloc a stream\n");
		return 0;

checkCuda(cudaMallocManaged(&ret, 1000000 * sizeof(int), cudaMemAttachHost))

memset((void *)ret, 0xAA, 1000000 * sizeof(int));

printf("after ret setting we have ret[1] == %d\n", ret[1]);


And can see that memset get stuck.

The execution environment is a new system 76 running Ubuntu 15.04, and GeForce GTX 980.

P.S. the same test on a different machine (a mac book pro (dual boot)) running Ubuntu 14.04 with CUDA 7.0 and GeForce GT 750M runs this test without any issues.

Please help :-)

Thank you.

Ubuntu 15.04 is not an officially supported distro for CUDA 7.

You might want to switch to Ubuntu 14.04

Tx. I suspect that this is the issue…

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