Add time retrieval latency profile to CLI diagnostics #2844
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guilhermelawless
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SergiySW
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Jul 14, 2020
wezrule
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Jul 16, 2020
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A slower clocksource can have significant impact on the performance of the node. I was faced with this issue in a laptop with unstable TSC which falls back to the slower HPET (almost two orders of magnitude slower).
The cause wasn't immediately apparent, only after profiling, so this PR adds a quick loop to
--diagnosticsto measure the latency in retrieving the current system time. The loop isn't optimized away even in O3. Only takes ~100ms total with TSC.For reference: