The invention relates to the field of printers, and discloses a printer which comprises a communication interface, a storer, a printing mechanism, and a controller. The communication interface is usedfor receiving multiple queued printing tasks; the storer is used for storing a mapping table of workloads and printing speeds; the controller is used for controlling the printing mechanism to executethe printing tasks; and the controller is configured to be used for analyzing a received current printing task and a next printing task so as to obtain a first workload and a second workload, when judging that the first workload is larger than a set threshold, retrieving the mapping table from the storer, and dividing the current printing task into multiple continuous sub tasks, controlling the printing speed according to the mapping table and the first workload, after executing the current sub task, executing the next sub task in a delayed mode, and when judging that the sum of a workload ofthe final sub task and the second workload is larger than the set threshold, after executing the final sub task, executing the next printing task in a delayed mode.