A method and apparatus of a device that coalesces the execution of several timers by scheduling the timers using a scheduling window is described. The device determines a scheduling window for each of several timers. The device selects a coalesced execution time that is within the scheduling window of the timers. The device coalesces the execution of the timers by scheduling the timers to execute at the coalesced execution time. The device can further coalesce multiple timers by opportunistic execution of the timers. In response to a detection of an opportunistic execution trigger event, the device receives multiple timers. The device selects a subset of the timers to execute based on an initial execution time and a latency time for each of the timers. The device schedules each of the subset of timers to execute during or before the opportunistic execution trigger event.