double t_start = dis_time(); //.... stuff to be timed ... double t_end = dis_time(); derr << "That took " << t_end - t_start << " seconds" << endl
dis_time returns a floating-point number of seconds, representing elapsed wall-clock time since some time in the past. The time in the past is guaranteed not to change during the life of the process. The user is responsible for converting large numbers of seconds to other units if they are preferred. This function is portable (it returns seconds, not ticks), it allows high resolution, and carries no unnecessary baggage. In a distributed environment, dis_time clocks are synchronized: different nodes return the same time value at the same instant.
seq_time is similar but the time returned is local to the node that called them and clocks are not synchronized: in a distributed environment, different nodes can return diferent local times, at different instant when the call to seq_time is reached.