embedded_files: freeup ram before upgrade

freeup as much ram as possible before upgrade to cause less bricks on 32Mb RAM devices.
Initial idea for freifunk-berlin#806

embedded-files/lib/update/freifunk-berlin_freeup-ram.sh

@@ -0,0 +1,24 @@
+echo "This is the Freifunk Berlin-script"
+
+MEMLIMIT=33554432   # 32MB
+SERVICES="cron pingcheck uhttpd rpcd odhcpd"        
+
+MEMFREE=$(cat /proc/meminfo |grep MemTotal|awk '{print $2}')
+
+ifdown ffuplink
+
+echo stopping non-essential services
+for service in $SERVICES; do
+  echo -n "${service} "
+  [ -x /etc/init.d/${service} ] && /etc/init.d/${service} running && { /etc/init.d/${service} stop; echo -n " ..stopped.. "; }
+done
+echo ""
+
+echo flushing files from /tmp
+rm >/dev/null -f /tmp/luci-indexcache*
+rm >/dev/null -rf /tmp/luci-modulecache
+
+
+echo end of Freifunk Berlin-script
+#exit 10
+