Abstract: An oil return method for multi-split air conditioner in heating comprises steps of: S1, adjusting operation frequency f0 of a compressor (11) to a first preset oil return frequency f1, and simultaneously, adjusting open degree S0 of each indoor throttling element (22) to a preset oil return open degree; S2, measuring operation parameters of the air conditioner; S3, judging whether the air conditioner operates abnormally, jumping to Step S4 if so, or jumping to Step S5 if not; S4, exiting from oil return process, adjusting the operation frequency f0 of the compressor (11) to a second preset oil return frequency f2, judging whether the air conditioner operates abnormally, existing from the oil return process if so, or jumping to Step S5 if not; S5, ending the oil return process when oil return time reaches the oil return time t2.

Abstract: A method is provided for memory releasing. The method includes obtaining a first memory space value of a terminal system, where the first memory space represents a size of current idle memory space on the terminal system. The method also includes requesting a memory space whose size equals to a second memory space value from the terminal system, where the second memory space value is greater than the first memory space value. Further, the method includes releasing occupied memory after the terminal system receives a memory space request and detects that the second memory space value is greater than the first memory space value. The method includes confirming allocation of the memory space whose size equals to the second memory space value. The method includes releasing the memory space whose size equals to the second memory space value as the idle memory space after receiving allocation confirmation of the memory space of the terminal system.