Document how to overwrite Buck's settings
Change-Id: I90bece92bf7a1ed72a24d014e42f9be581361856
diff --git a/Documentation/dev-buck.txt b/Documentation/dev-buck.txt
index 0acf04a..a41a821 100644
--- a/Documentation/dev-buck.txt
+++ b/Documentation/dev-buck.txt
@@ -332,6 +332,31 @@
[-] BUILDING...FINISHED 0.2s
----
+Overwrite Buck's settings
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+In the latest version of Buck the wrapper script `buck_common` will source
+one of these files (if they exist): /etc/buck.conf, $HOME/.buck/buck.conf or
+$HOME/.buckrc. The trivial case to overwrite the Buck's default 1GB heap size:
+
+----
+ cat > $HOME/.buckrc <<EOF
+ export BUCK_EXTRA_JAVA_ARGS="\
+ -XX:MaxPermSize=512m \
+ -Xms8000m \
+ -Xmx16000m"
+ EOF
+----
+
+Or to debug BUCK, set BUCK_DEBUG_MODE to anything non-empty, then connect to
+port 8888:
+
+----
+ cat > $HOME/.buckrc <<EOF
+ export BUCK_DEBUG_MODE="yes"
+ EOF
+----
+
GERRIT
------
Part of link:index.html[Gerrit Code Review]
