From nobody Tue Oct 28 01:52:13 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1515088803419475.3361378056487; Thu, 4 Jan 2018 10:00:03 -0800 (PST) Received: from localhost ([::1]:56626 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eX9oA-0007GD-EJ for importer@patchew.org; Thu, 04 Jan 2018 13:00:02 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47754) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eX9lQ-0004kr-C7 for qemu-devel@nongnu.org; Thu, 04 Jan 2018 12:57:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eX9lM-00065d-Av for qemu-devel@nongnu.org; Thu, 04 Jan 2018 12:57:12 -0500 Received: from gw03.mail.saunalahti.fi ([195.197.172.111]:55812) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eX9lM-00063i-1r for qemu-devel@nongnu.org; Thu, 04 Jan 2018 12:57:08 -0500 Received: from guava.gson.org (a91-152-17-19.elisa-laajakaista.fi [91.152.17.19]) by gw03.mail.saunalahti.fi (Postfix) with ESMTP id 6A35120761; Thu, 4 Jan 2018 19:56:59 +0200 (EET) Received: by guava.gson.org (Postfix, from userid 101) id 27D3998B4A0; Thu, 4 Jan 2018 19:56:58 +0200 (EET) MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Message-ID: <23118.27370.136663.284087@guava.gson.org> Date: Thu, 4 Jan 2018 19:56:58 +0200 To: qemu-devel@nongnu.org X-Mailer: VM 8.2.0b under 25.3.1 (x86_64--netbsd) From: Andreas Gustafsson X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 195.197.172.111 Subject: [Qemu-devel] [PATCH] slirp: disable Nagle in outgoing connections X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Samuel Thibault , Kamil Rytarowski , Jan Kiszka Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" slirp: disable Nagle in outgoing connections When setting up an outgoing user mode networking TCP connection, disable the Nagle algorithm in the host-side connection. Either the guest is already doing Nagle, in which case there is no point in doing it twice, or it has chosen to disable it, in which case we should respect that choice. This change speeds up GDB remote debugging over TCP over user mode networking (with GDB runing on the guest) by multiple orders of magnitude, and has been part of the local patches applied by pkgsrc since 2012 with no reported ill effects. Signed-off-by: Andreas Gustafsson Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- slirp/tcp_subr.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c index da0d53743f..8d0f94b75f 100644 --- a/slirp/tcp_subr.c +++ b/slirp/tcp_subr.c @@ -416,6 +416,8 @@ int tcp_fconnect(struct socket *so, unsigned short af) socket_set_fast_reuse(s); opt =3D 1; qemu_setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(opt)); + opt =3D 1; + qemu_setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt)); =20 addr =3D so->fhost.ss; DEBUG_CALL(" connect()ing") --=20 2.15.1