Nick Hill 250b279bd9 Epoll: Avoid redundant EPOLL_CTL_MOD calls (#9397) ... Motivation Currently an epoll_ctl syscall is made every time there is a change to the event interest flags (EPOLLIN, EPOLLOUT, etc) of a channel. These are only done in the event loop so can be aggregated into 0 or 1 such calls per channel prior to the next call to epoll_wait. Modifications I think further streamlining/simplification is possible but for now I've tried to minimize structural changes and added the aggregation beneath the existing flag manipulation logic. A new AbstractChannel#activeFlags field records the flags last set on the epoll fd for that channel. Calls to setFlag/clearFlag update the flags field as before but instead of calling epoll_ctl immediately, just set or clear a bit for the channel in a new bitset in the associated EpollEventLoop to reflect whether there's any change to the last set value. Prior to calling epoll_wait the event loop makes the appropriate epoll_ctl(EPOLL_CTL_MOD) call once for each channel who's bit is set. Result Fewer syscalls, particularly in some auto-read=false cases. Simplified error handling from centralization of these calls.		2019-08-19 09:06:41 +02:00
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main	Epoll: Avoid redundant EPOLL_CTL_MOD calls (#9397)	2019-08-19 09:06:41 +02:00
test/java/io/netty/channel/epoll	Do not cache local/remote address when creating EpollDatagramChannel with InternetProtocolFamily (#9436)	2019-08-11 09:09:26 +02:00