move chroot and pbuilder builds to tmpfs

For this change update_jdn.sh will only work well, if jenkins is not
running. It avoids breaking running builds at the cost of potentially
not applying configuration. The changes are:

 * /srv/workspace becomes a tmpfs mounted location
 * /etc/init.d/jenkins-workspace creates subdirectories on that tmpfs
 * Old locations for chroots and pbuilder are moved using symlinks.

2 files changed, 56 insertions, 1 deletions

diff --git a/etc/init.d/jenkins-workspace b/etc/init.d/jenkins-workspace
new file mode 100755
index 00000000..128d828c
--- /dev/null
+++ b/etc/init.d/jenkins-workspace
@@ -0,0 +1,22 @@
+#!/bin/sh
+### BEGIN INIT INFO
+# Provides:		jenkins-workspace
+# Required-Start:	$remote_fs
+# Required-Stop:	$remote_fs
+# Default-Start:	2 3 4 5
+# Default-Stop:
+# X-Start-Before:	jenkins
+# Short-Description:	Create jenkins workspace directory structure
+### END INIT INFO
+
+WORKSPACE=/srv/workspace
+
+case "$1" in
+	start)
+		echo "Creating jenkins workspace"
+		mkdir "$WORKSPACE/chroots"
+		chown jenkins:jenkins "$WORKSPACE/chroots"
+		mkdir "$WORKSPACE/pbuilder"
+		echo done
+	;;
+esac
diff --git a/update_jdn.sh b/update_jdn.sh
index 99438d44..f256c15a 100755
--- a/update_jdn.sh
+++ b/update_jdn.sh
@@ -13,14 +13,46 @@ explain() {
 	echo
 }
 
+mkdir -p /srv/workspace
+
+if ! grep -q '^tmpfs\s\+/srv/workspace\s'; then
+	echo "tmpfs		/srv/workspace	tmpfs	defaults,size=60g	0	0" >> /etc/fstab
+fi
+
+if ! mountpoint -q /srv/workspace; then
+	if test -z "$(ls -A /srv/workspace)"; then
+		mount /srv/workspace
+	else
+		echo "mountpoint /srv/workspace is non-empty"
+	fi
+fi
+
 # make sure needed directories exists
-for directory in  /srv/jenkins /chroots /schroots; do
+for directory in  /srv/jenkins /schroots; do
 	if [ ! -d $directory ] ; then
 		sudo mkdir $directory
 		sudo chown jenkins.jenkins $directory
 	fi
 done
 
+if ! test -h /chroots; then
+	rmdir /chroots || rm -f /chroots # do not recurse
+	if test -e /chroots; then
+		echo could not clear /chroots
+	else
+		ln -s /srv/workspace/chroots /chroots
+	fi
+fi
+
+if ! test -h /var/cache/pbuilder/build; then
+	rmdir /var/cache/pbuilder/build || rm -f /var/cache/pbuilder/build
+	if test -e /var/cache/pbuilder/build; then
+		echo could not clear /var/cache/pbuilder/build
+	else
+		ln -s /srv/workspace/pbuilder /var/cache/pbuilder/build
+	fi
+fi
+
 #
 # install packages we need
 # (more or less grouped into more-then-nice-to-have, needed-while-things-are-new, needed)
@@ -42,6 +74,7 @@ sudo apt-get build-dep installation-guide
 #
 cd $BASEDIR
 sudo cp -r etc/* /etc
+update-rc.d jenkins-workspace defaults
 
 #
 # more configuration than a simple cp can do