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[lesismal]

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[lesismal]

Socket

1. epoll/kqueue: clear fd from poller automatically by syscall.Close will.
2. Add flow control for write cache flush to avoid large buffer write failure.
3. Optimize the write cache using buffers to avoid a single large buffer cache.

HTTP:

1. Change body to [][]byte to avoid single large buffer usage.
2. Optimize body calculation.
3. Add MaxHTTPBodySize config.
4. add Client.Dial configuration.
5. add Engine.SetETAsyncRead/SetLTSyncRead.

Websocket

1. Add Lock for parsing logic.
2. Optimize session consistency.