Fix new scheduler loop #747
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win-t
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Apr 9, 2020
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| // If another thread is already blocked on the reactor, there is no point in keeping | ||
| // the current thread around since there is too little work to do. | ||
| if sched.polling { | ||
| thread::sleep(Duration::from_micros(10)); | ||
| continue; | ||
| break; | ||
| } |
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I'm not sure, terminating the thread is a good idea, what will happen when the load is increasing? no new thread will be created
simple sleep like this will end up with single thread with no way to recover the worker thread
task::spawn(async {
loop {
task::sleep(Duration::from_secs(1)).await;
io::stdout().write_all(b"Hello World\n").await.unwrap();
}
})
.await;There was a problem hiding this comment.
We can not go back to the sleep & continue, it regresses performance even further, so we need to find a better solution.
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The correct fix as far as I understand is to bring back the dynamic restarting of machines: #748
dignifiedquire
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Apr 10, 2020
Even if we do not make use of the progress blocking, we do need to make use of the dynamic restarting of machines as far as I understand. Keeps the perf, while removing the regression from #747
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This now matches more closely the logic as implemented in #631, and fixes the performance regression as far as I have observed.
Closes #746