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RE: Tune reader_thread poll timeout value
>I'm missing something. Why does the second item not moot the first?
>IOW, if we poll with a 5s timeout, why wouldn't the timer.s(1) reports
>wake up the ppoll() to avoid waiting till 5s?
>ppoll() wakes-up only when 1 buffer is full. timer.s(1) wakes-up whatever kernel thread (by the way, I
>should check that with contextswitch trace) but trace throughput is very low. After 5 seconds, ppoll
>time-outs and the 5 traces done by timer.s(1) at every second are dumped.
>When I say "do not use", it is really for interactivity with terminal. People may want to get some
>small metric every s, but 5 metrics will be displayed every 5s. Of course, for a log read later, you
>So, yes, people should be cautious with this but well, this is for embedded platforms and this is
>really our goal.
Does it make sense then ? In case of low throughput use cases, we have been for a long time dumping buffers only every few s isntead of 200us at the cost of printing latency. Rare cases but needed.
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