setstream,1;
NullKernel; streamsync;
loop,100000; NullKernel; streamsync; endloop,1;

loop,100000; H2D;  streamsync; NullKernel; streamsync; endloop,1;

loop,100000; H2D;  streamsync; NullKernel; streamsync; D2H;  streamsync; endloop,1;