Part Number:AM5728
Tool/software: Linux
Since 5728 support Preempt RT Linux ,so I made 2 tests.
The first one is ti-processor-sdk-linux-rt-am57xx-evm-03.03.00.04 version ,which includes linux-rt-4.4.41+gitAUTOINC+968d071ce9-g968d071ce9 kernel.
After installtion, the
cyclictest -t 5 -p 80 -n gives the result
T:0(1487) P:80 I:1000 C:7326365 Min:8 Act:9 Avg: 9 Max:37
T:1(1488) P:80 I:1500 C:4884243 Min:7 Act:9 Avg: 9 Max:29
T:2(1489) P:80 I:2000 C:3663177 Min:8 Act:9 Avg: 9 Max:49
T:3(1490) P:80 I:2500 C:2930542 Min:8 Act:9 Avg: 9 Max:35
T:4(1491) P:80 I:3000 C:2442118 Min:8 Act:9 Avg: 9 Max:35
The result is excellent in max latency.
However, the second test on ti-processor-sdk-linux-rt-am57xx-evm-04.03.00.05, which includes linux-rt-4.9.69+gitAUTOINC+7069a470d5-g7069a470d5 kernel, is bad. The result is
T:0(954) P:80 I:1000 C:91521 Min:7 Act:20 Avg: 15 Max:6653
T:1(955) P:80 I:1500 C:61067 Min:8 Act:12 Avg: 14 Max:7155
T:2(956) P:80 I:2000 C:45673 Min:8 Act:9 Avg: 22 Max:6690
T:3(957) P:80 I:2500 C:36712 Min:8 Act:11 Avg: 10 Max:6202
T:4(958) P:80 I:3000 C:30597 Min:8 Act:12 Avg: 10 Max:281
It seems that the Preempt RT patch in linux is not working at all, I want to know the reason. Is that the problem of kernel itself?
Thank you.
