1. Method for executing instruction sequences simultaneously in several processors ( 3, 4, 5 ) of a multiprocessor machine ( 1 ), characterized in that it comprises: a first step ( 8 ) in which a single processor operating system is booted in a first processor ( 2 ); a second step ( 9 ) in which the first processor ( 1 ) orders at least one other processor ( 3 ) of the machine, called an application processor, to execute one or more instruction sequences ( 17, 18, 19 ) under the control of said first processor.