Fermi L2 cache hit latency?

Question

Does anyone know related information about L2 cache in Fermi? I have heard that it is as slow as global memory, and the use of L2 is just to enlarge the memory bandwidth. Bu

Answer 1

This thread in the nvidia has some measurements for performance characteristica. While it is not official information, and probably not 100% exact, it gives at least some indication for the behaviour, so I thought it might be useful here (measurements in clockcycles):

1020 non-cached (L1 enabled but not used)

1020 non-cached (L1 disabled)

365 L2 cached (L1 disabled)

88 L1 cached (L1 enabled and used)

Another post in the same thread gives those results:

1060 non-cached

248 L2

18 L1