1. A method for analysis of thread latency, comprising: determining a thread of interest; computing a summation of time periods in which the thread of interest stays in a run queue to determine a thread in-run-queue time; computing a summation of time periods in which the thread of interest is preempted by other threads to determine a thread preempted time; determining a ratio of the thread preempted time to the thread in-run-queue time; determining that the thread latency is caused by the power management policy if the ratio of the thread preempted time to the thread in-run-queue time is lower than a threshold; and generating a system control policy according to the ratio, the thread preempted time and the thread in-run-queue time, wherein system control policy includes at least one of a thread priority assignment policy and a power management policy.