1. A method for synchronizing two or more engines in a graphics processing unit (GPU), the method comprising: writing an event value representing a command issued to a predetermined engine into an element of an event memory; modifying a content of the event memory containing the event value recognizing a completion of the command execution by the engine; and reading the modified content of the event memory by a central processing unit (CPU) to acquire the command execution status, wherein the CPU coordinates command issuing to all the engines based on the command execution status of each engine.