Embodiments include accelerating capture of a system dump at system failure in a computer system. A method includes capturing a system snapshot that includes data from real memory frames of the computer system and storing the system snapshot in a storage. The method also includes monitoring periodically a change between the data in the system snapshot and a current state of the real memory frames of the computer system and updating the system snapshot according to the changed real memory frames based on a rate of change of the real memory frames. Further, in response to encountering the system failure, the snapshot is updated based on a delta between the system snapshot and the current state of the real memory frames. The snapshot on the storage is used as the system dump. The present document further describes examples of other aspects such as systems, computer products.