device organization

[martman]

Hello.

Im not sure if I full get the organization of a CUDA device yet and I’m trying understand the output of deviceQuery.

Does this mean I can have 65535 blocks total on one big grid with 512 threads running in each block? Does this also mean that at any point I actually have 32 threads running at once?

Thanks

There is 1 device supporting CUDA

Device 0: “GeForce 8800 GTX”

Major revision number:                        1

Minor revision number:                        0

Total amount of global memory:                            804978688 bytes

Total amount of constant memory:                      65536 bytes

Total amount of shared memory per block:      16384 bytes

Total number of registers available per block:        8192

Warp size:                                    32

Maximum number of threads per block:          512

Maximum sizes of each dimension of a block:    512 x 512 x 64

Maximum sizes of each dimension of a grid:    65535 x 65535 x 1

Maximum memory pitch:                          262144 bytes

Texture alignment:                            256 bytes

Clock rate:                                    1350000 kilohertz

Test PASSED

Press ENTER to exit…

[MisterAnderson42]

Well, you can run up to 65535 * 65535 blocks in a single call, which is a lot. And 32 is just the warp size. G80 has 16 multiprocessors each of which can keep 24 warps running in an interleaved fashion => the device is running 162632 threads at once.