benchmark.thread_metric.synchronization results deviation observed on mec172xevb_assy6906

[golowanow]

Describe the bug

mec172xevb_assy6906/mec172x_nsz board shows results for benchmark.thread_metric.synchronization with significantly larger deviation in comparison to what is observed on other platforms.
For example, the benchmark daily probe results for a mec17 board and another board with rather typical statistics for comparison (in the attachments).

To Reproduce
Run tests/benchmarks/thread_metric several times (10-20) to collect results; each benchmark run records 3 measurements by default. Calculate standard deviation for each run and compare deviations between the runs. The difference between these deviations on mec172 might be quite large e.g. 94% in case of 14/Apr vs. 15/Apr.

Expected behavior
A small difference (<10%) between benchmark.thread_metric.synchronization run's deviations.

Impact
unknown

Logs and console output

mec172xevb_assy6906 -

some other board -

Environment (please complete the following information):

• OS: Linux
• Toolchain: Zephyr SDK
• Commit SHA or Version used: v4.1.0-2642-g0648e49bf0f5