METHOD FOR EVENT-BASED SIMULATION OF A SYSTEM
A method for event-based simulation of a system, the simulation comprising a first computing unit and at least one second computing unit, the first computing unit has a simulation time, the second processor has an operating system layer and an application layer. The second computing unit has a system time in the operating system layer, with at least the second computing unit executing a simulation application. At least one simulation object is executable on the simulation application, and the first computing unit manages an event queue, with at least one event per simulation step being listed in the event queue. The event is associated with a process to be executed by the simulation object and a simulation time provided for execution of the process.
1 . A method for event-based simulation of a system, the method comprising:
providing a computer system to perform the simulation, the computer system comprising a first computing unit and at least one second computing unit, the first computing unit having a simulation time, the second computing unit having an operating system layer and an application layer, the second computing unit having a system time in the operating system layer;
performing, via the second computing unit, a simulation application, at least one simulation object being executed on the simulation application; and
managing, via the first computing unit, an event queue, wherein in the event queue at least one event is listed for each simulation step, and the at least one event is associated with a process to be executed via the simulation object and with a simulation time point provided for the execution of the process;
providing the second computing unit with a virtual clock generator;
transmitting, via the first computing unit, a start signal to the virtual clock generator for executing the next simulation step in the second computing unit;
incrementing, based on a time difference between a past simulation step and the simulation time, the system time of the second computing unit; and
executing the upcoming process at the simulation time point associated with the process.
2 . The method according to claim 1 , wherein the time difference between the past simulation step and the simulation time is calculated by the first computing unit and is transmitted to the second computing unit with the start signal.
3 . The method according to claim 1 , wherein the simulation time is transmitted by the first computing unit with the start signal to the second computing unit and the second computing unit calculates the time difference between the past simulation step and the simulation time.
4 . The method according to claim 1 , wherein the first computing unit has a first network interface and the second computing unit has a second network interface, wherein the first and second network interfaces are interconnected via a bus system, and wherein the transmission of the start signal takes place via the network interface and the bus system.
5 . The method according to claim 1 , wherein the simulation objects are executed on the same operating system as the associated simulation application.
6 . The method according to claim 5 , wherein the simulation objects are executed in a closed environment, wherein the simulation objects in the closed environment are granted access to a first set of hardware resources of the computing unit associated with the simulation application, and wherein the first set of hardware resources are defined by the simulation application.
7 . The method according to claim 6 , wherein the simulation objects in the closed environment are denied access to a second set of hardware resources of the computing units associated with the simulation application.
8 . The method according to claim 5 , wherein at least two of the simulation objects each have a virtual network interface, wherein the virtual network interface is able to receive or send calculation results via a virtual bus system.
9 . The method according to claim 5 , wherein at least one of the simulation objects on the first or second computing unit is a virtual control device.
10 . The method according to claim 8 , wherein the calculation results is sent from the virtual network interface of a first computing unit via a network tunnel to the virtual network interface of a second computing unit.
11 . The method according to claim 5 , wherein the computing units are physical computing nodes.
12 . The method according to claim 7 , wherein at least one computing unit is a virtual computing node, the operating system of the respective computing unit being executed by a hypervisor.
13 . The method according to claim 1 , wherein the virtual clock generator is implemented in the application level.
14 . The method according to claim 1 , wherein the virtual clock generator is implemented at the operating system level.