selector: dynamically adjust event count#637
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arnetheduck wants to merge 2 commits into
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When fetching events with epoll/kqueue, we currently use a fixed size array to fetch system events. Taking an idea from [libevent](https://github.com/libevent/libevent/blob/48296514d8fd9c0b3812b11d45ad80b0c002c14e/epoll.c#L568), we can instead dynamically grow the number of events fetched as the system comes under load thus reducing the number of poll calls, allowing more work to be done per batch. The change also has the effect that data that already arrived at the time of the poll call gets processed before timers are fired - this means that timeouts are less likely to be triggered unfairly due to event queueing order and the time it takes to process each event. * increase max events per loop to 4096 (same as libevent) * reduce initial event list allocation to 32 * get rid of `ReadyKey.errorCode` which is unused
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When fetching events with epoll/kqueue, we currently use a fixed size array to fetch system events.
Taking an idea from
libevent, we can instead dynamically grow the number of events fetched as the system comes under load thus reducing the number of poll calls, allowing more work to be done per batch.
The change also has the effect that data that already arrived at the time of the poll call gets processed before timers are fired - this means that timeouts are less likely to be triggered unfairly due to event queueing order and the time it takes to process each event.
ReadyKey.errorCodewhich is unused