A Hardware/Software Platform for Real-time Ethernet Cluster Simulation in OMNeT++

Transcription

1 A Hardware/Software Platform for Real-time Ethernet Oleg Karfich Florian Bartols Till Steinbach Franz Korf Thomas C. Schmidt {oleg.karfich, florian.bartols, till.steinbach, korf, 6th International Workshop 5 March 2013, Cannes NET

2 Software simulation is established during design and reconfiguration phases Cluster simulation is useful during integration and setup phases Environments for cluster simulation need generally expensive real-time hardware platforms 3 / 14

3 Cluster Simulation real system-under-test (SUT) RTEthernet Cluster Simulation Time-triggered Ethernet Cluster Simulator Real SUT connected via communication interface Cluster simulator simulates not available parts 5 / 14

4 Time-triggered Ethernet Mixed critical applications through IEEE 802 networks Extension to standard switched Ethernet Provides three traffic classes: 1 Time-triggered (TT) highest priority, time-triggered, cyclic, requires synchronised time 2 Rate-constrained (RC) event-triggered, bandwidth-based 3 Best-effort (BE) lowest priority, standard Ethernet Cluster Simulation Time-triggered Ethernet 6 / 14

5 Overview of the Cluster Simulation HW/SW Platform Host PC Core 0 Core 1 Simulation MPI DPM Communicator PCI Bus DPM PCI DPM IRQ Microcontroller Scheduler TU Ethernet Userspace Kernelspace IRQhandled Linux with RT-Patch notify Generic UIO Driver Microcontroller ISR IRQ- Handler 8 / 14

6 Latency L a te n c y [µ s ] Latency Jitter F ra m e s iz e [b y te ] Latency is 186.4µs for minimal sized frames 10 / 14

7 Jitter D iv e rg e n c e fro m C y c le [µ s ] Latency Jitter C y c le [# ] Using off-the-shelf hardware results in a higher jitter 11 / 14

8 Replacing the microcontroller by a specialised NIC Dedicated hardware time stamping unit Higher bandwidth Multicore parallelisation of the simulation model Analysing different Linux real-time approaches 13 / 14

9 Thank you for your attention! Website of Co research group: 14 / 14