Netty provides both NIO transport and native (epoll/bsd) transport as described here: https://netty.io/wiki/native-transports.html .

By default, jasync will discover if native transport is supported and will use it, and will fallback to NIO. In order to configure that in jasync Connection and ConnectionFactory has group parameter that can have one of these values:

• EpollEventLoopGroup
• KQueueEventLoopGroup
• NioEventLoopGroup

Unix Domain Socket allows connecting via local socket file. This is supported only with native transport (not NioEventLoopGroup). More info in https://github.com/jasync-sql/jasync-sql/issues/175.