This usually means it is using the wrong timer in a deeper idle state.
Some idle states cannot be woken up by e.g. the APIC timer and then
you get that effect: you only make progress when you wake up the
CPU in some other way like pressing a key. Then on wake up the
timers get processed.
This is usually a bug in the kernel timer selection. It should be chosing
a timer that always wakes up from the deepest idle state used.
You should post the full boot log
-Andi
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