Can SIFT run in realtime? What is the best possible runtime for extracting SIFT keypoints and Descriptors?
I know it depends on #keypoints extracted. So, say for image of size 640x640, the code that I have been using requires around 3 seconds for description of ~2000 keypoints.

What is the best runtime achieved and how (on similar grounds)? How can I make it run in realtime?
Is hadoop with 100 clusters a solution?
SIFT implemented on a GPU can run in realtime!

http://cs.unc.edu/~ccwu/siftgpu/