Abstract: When target data is to be accessed, a computing node determines whether the target data meets a computing pushdown condition. When the target data meets the computing pushdown condition, send a data access request to a storage node. After receiving the data access request, the storage node obtains a dataset to which the target data belongs, performs the computing service based on the computing indication, accesses the target data in the dataset, and feeds back an access result to the computing node.

Abstract: Embodiments of an optical detection apparatus are disclosed which may include one or more of a waveguide, a trench formed in the waveguide, a reflective surface, and a photodetector. The waveguide may be formed in a semiconductor substrate to propagate an optical signal received at a first end of the waveguide. The trench may also be formed in the waveguide having a first sidewall and a second sidewall, the first and second sidewalls forming first and second angles with the waveguide's propagation direction. The second sidewall may include a reflective surface formed thereon. The photodetector may be configured to receive an optical signal propagated in the waveguide, through the first sidewall and reflected from the reflective surface on the second sidewall.