commit 3f7f3221dff1a4b2bac3a2dc3e39f732d44fdf2a
author JP Abgrall <jpa@google.com> Fri Feb 21 12:05:20 2014 -0800
committer JP Abgrall <jpa@google.com> Wed Mar 12 20:22:47 2014 -0700
tree 0acbccb895ee5d0216be169c84fa8a88cb91e218
parent a796168da0ea139fe7312678f5031cd96c50097c

ConnectivityService: add support to set TCP initial rwnd

The value for the TCP initial receive window comes from,
in order,

kernel
  /proc/sys/net/ipv4/tcp_default_init_rwnd

init.rc (via properties)
  net.tcp.default_init_rwnd

properties
  net.tcp.default_init_rwnd

gservices
  Settings.Global.TCP_DEFAULT_INIT_RWND

Bug: 12020135
Change-Id: I0e271be19472900fa9f3bab037d53383ec014a9e

services/java/com/android/server/ConnectivityService.java

diff --git a/services/java/com/android/server/ConnectivityService.java b/services/java/com/android/server/ConnectivityService.java
index 83a3bfd..6a28fd6 100644
--- a/services/java/com/android/server/ConnectivityService.java
+++ b/services/java/com/android/server/ConnectivityService.java
@@ -2757,6 +2757,15 @@
             }
             setBufferSize(bufferSizes);
         }
+
+        final String defaultRwndKey = "net.tcp.default_init_rwnd";
+        int defaultRwndValue = SystemProperties.getInt(defaultRwndKey, 0);
+        Integer rwndValue = Settings.Global.getInt(mContext.getContentResolver(),
+            Settings.Global.TCP_DEFAULT_INIT_RWND, defaultRwndValue);
+        final String sysctlKey = "sys.sysctl.tcp_def_init_rwnd";
+        if (rwndValue != 0) {
+            SystemProperties.set(sysctlKey, rwndValue.toString());
+        }
     }
 
     /**