From mboxrd@z Thu Jan 1 00:00:00 1970 From: Francois Saint-Jacques Subject: [patch] socket.7: Document SO_INCOMING_CPU Date: Fri, 17 Feb 2017 23:06:50 -0500 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Return-path: Sender: linux-man-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org This socket option is undocumented. Applies on the latest version (man-pages-4.09-511). diff --git a/man7/socket.7 b/man7/socket.7 index 3efd7a5d8..1a3ffa253 100644 --- a/man7/socket.7 +++ b/man7/socket.7 @@ -490,6 +490,26 @@ flag on a socket operation. Expects an integer boolean flag. .TP +.BR SO_INCOMING_CPU " (getsockopt since Linux 3.19, setsockopt since Linux 4.4)" +.\" getsocktop 2c8c56e15df3d4c2af3d656e44feb18789f75837 +.\" setsocktop 70da268b569d32a9fddeea85dc18043de9d89f89 +Sets or gets the cpu affinity of a socket. Expects an integer flag. +.sp +.in +4n +.nf +int cpu = 1; +socklen_t len = sizeof(cpu); +setsockopt(fd, SOL_SOCKET, SO_INCOMING_CPU, &cpu, &len); +.fi +.in +.sp +The typical use case is one listener per RX queue, as the associated listener +should only accept flows handled in softirq by the same cpu. This provides +optimal NUMA behavior and keep cpu caches hot. +.TP .B SO_KEEPALIVE Enable sending of keep-alive messages on connection-oriented sockets. Expects an integer boolean flag. -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html