8.3. Runtime Instrumentation Testing - N1SDP

For this test we used the N1 System Development Platform (N1SDP), which contains an SoC consisting of two dual-core Arm N1 clusters.

The following source trees were used:

Please see the Runtime Instrumentation Testing Methodology page for more details. The tests were ran using the tf-psci-lava-instr/n1sdp-runtime-instrumentation,n1sdp-runtime-instrumentation:n1sdp-fip.tftf-firmware configuration in CI.

8.3.1. Results

8.3.1.1. CPU_SUSPEND to deepest power level

CPU_SUSPEND latencies (ns) to deepest power level in parallel (v2.14)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

3380.0(+1.81%)

12480.0(-7.00%)

340.0(+21.43%)

0

1

3840.0(-4.48%)

17940.0(-1.10%)

220.0(-21.43%)

1

0

2560.0(-5.19%)

17140.0(-1.38%)

160.0(-38.46%)

1

1

3040.0(+2.70%)

9960.0(-8.29%)

140.0(-46.15%)

CPU_SUSPEND latencies (ns) to deepest power level in parallel (v2.13)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

3320.00

13420.00

280.00

0

1

4020.00

18140.00

280.00

1

0

2700.00

17380.00

260.00

1

1

2960.00

10860.00

260.00

CPU_SUSPEND latencies (ns) to deepest power level in serial (v2.14)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

1640.0(+1.23%)

10140.0

300.0

0

1

1980.0(+6.45%)

10440.0(-1.69%)

280.0

1

0

1640.0(-8.89%)

10340.0(+1.77%)

160.0(-50.00%)

1

1

2280.0(+5.56%)

10560.0

600.0(+20.00%)

CPU_SUSPEND latencies (ns) to deepest power level in serial (v2.13)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

1620.00

10140.00

300.00

0

1

1860.00

10620.00

280.00

1

0

1800.00

10160.00

320.00

1

1

2160.00

10600.00

500.00

8.3.1.2. CPU_SUSPEND to power level 0

CPU_SUSPEND latencies (ns) to power level 0 in parallel (v2.14)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

1380.0(+72.50%)

10600.0(-11.52%)

240.0(-7.69%)

0

1

1660.0(+7.79%)

15880.0(-3.41%)

140.0(-46.15%)

1

0

1640.0(+1.23%)

15200.0(-5.59%)

140.0(-53.33%)

1

1

1780.0(-1.11%)

9880.0(-6.26%)

140.0(-30.00%)

CPU_SUSPEND latencies (ns) to power level 0 in parallel (v2.13)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

800.00

11980.00

260.00

0

1

1540.00

16440.00

260.00

1

0

1620.00

16100.00

300.00

1

1

1800.00

10540.00

200.00

CPU_SUSPEND latencies (ns) to power level 0 in serial (v2.14)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

1560.0(+8.33%)

9680.0(-2.22%)

300.0

0

1

1900.0(+9.20%)

10380.0

280.0

1

0

1760.0(-2.22%)

10220.0(+1.79%)

340.0

1

1

1760.0(-10.20%)

10500.0

140.0(-68.18%)

CPU_SUSPEND latencies (ns) to power level 0 in serial (v2.13)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

1440.00

9900.00

300.00

0

1

1740.00

10400.00

280.00

1

0

1800.00

10040.00

340.00

1

1

1960.00

10460.00

440.00

8.3.1.3. CPU_OFF on all non-lead CPUs

CPU_OFF on all non-lead CPUs in sequence then, CPU_SUSPEND on the lead core to the deepest power level.

CPU_OFF latencies (ns) on all non-lead CPUs (v2.14)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

1700.0(+3.66%)

10020.0(-2.15%)

300.0

0

1

14440.0(+3.74%)

17140.0(-3.16%)

360.0(+20.00%)

1

0

13680.0(+1.03%)

16680.0

260.0(-13.33%)

1

1

14260.0

17600.0(-3.72%)

300.0

CPU_OFF latencies (ns) on all non-lead CPUs (v2.13)

Cluster

Core

Powerdown

Wakeup

Cache Flush

0

0

1640.00

10240.00

300.00

0

1

13920.00

17700.00

300.00

1

0

13540.00

16740.00

300.00

1

1

14120.00

18280.00

300.00

8.3.1.4. CPU_VERSION in parallel

CPU_VERSION latency (ns) in parallel on all cores (v2.14)

Cluster

Core

Latency

0

0

140.0(+16.67%)

0

1

240.0(+20.00%)

1

0

220.0(+10.00%)

1

1

260.0(+8.33%)

CPU_VERSION latency (ns) in parallel on all cores (v2.13)

Cluster

Core

Latency

0

0

120.00

0

1

200.00

1

0

200.00

1

1

240.00


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