Techniques recognize reducible contents in data to be written. The techniques involve receiving information related to data to be written, the information indicating that the data to be written comprises reducible contents, the reducible contents comprising data with a first reduction pattern. The techniques further involve recognizing the reducible contents in the data to be written based on the information. The techniques further involve reducing the reducible contents based on the first reduction pattern. With such techniques, active I/O pattern recognition with communication between applications and storage devices may be accomplished. In addition, with such techniques, it is easy/simple to expand recognizable new patterns, and I/O pattern limitations in standard approaches no longer exist.