From: Thomas H. P. Andersen <phomes@gmail.com>
Date: Thu, 31 May 2018 11:30:10 +0000 (+0200)
Subject: sysctl.d: request ECN on both in and outgoing connections (#9143)
X-Git-Tag: v239~174
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6f130e85c76cfc2c58ba31f90d2ac3800866c1dd;p=thirdparty%2Fsystemd.git

sysctl.d: request ECN on both in and outgoing connections (#9143)

To further avoid bufferbloat Explicit Congestion Notification (ECN)
should be enabled for both in and outgoing connections. The kernel
default is to enable it when requested for incoming connections, but
not to request it on outgoing connections. This patch enables it for
both.

A long time ago enabling these was causing problems, but these issues
have since been dealt with.

Fixes #9087.
---

diff --git a/sysctl.d/50-default.conf b/sysctl.d/50-default.conf
index e263cf06284..b67ae87ca6b 100644
--- a/sysctl.d/50-default.conf
+++ b/sysctl.d/50-default.conf
@@ -33,6 +33,9 @@ net.ipv4.conf.all.promote_secondaries = 1
 # Fair Queue CoDel packet scheduler to fight bufferbloat
 net.core.default_qdisc = fq_codel
 
+# Request Explicit Congestion Notification (ECN) on both in and outgoing connections
+net.ipv4.tcp_ecn = 1
+
 # Enable hard and soft link protection
 fs.protected_hardlinks = 1
 fs.protected_symlinks = 1