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Set EventLoopGroup ioRatio to 100
Motivation: Netty's EventLoop implementations use ioRatio in an attempt to balance the amount of time spent executing I/O related tasks and executed/scheduled tasks. However executing the executed tasks often result in I/O (e.g. write operations) and scheduled tasks are often time sensitive. Delaying execution of these tasks may increase latency while offloading is enabled and delay scheduled tasks on the EventLoop. Waking up the event loop can be relatively expensive so we amortize that cost by processing more events. This comes with the trade-off that reading (or writing to sockets where SND_BUF was full but now has space) could potentially be delayed if the cardinality/cost of executed/scheduled tasks is high. However by default offloading doesn't execute user code so folks would have to opt-in to run code on the EventLoop.
Modifications:
- Set ioRatio to 100 so that all executed/scheduled tasks are serviced on each wakeup.
Result: Scheduled writes and timer tasks execute in more timely fashion.
Once https://github.com/netty/netty/pull/12126 is available this can be perf tested.
