-# "APT::Archives::MaxSize",
-# - Set maximum size of the cache in MB (0=disable). If the cache
-# is bigger, cached package files are deleted until the size
-# requirement is met (the biggest packages will be deleted
-# first).
+# APT::Periodic::CleanInterval "0";
+# - Do "apt-get clean" every n-days (0=disable)
+#
+# APT::Periodic::Verbose "0";
+# - Send report mail to root
+# 0: no report (or null string)
+# 1: progress report (actually any string)
+# 2: + command outputs (remove -qq, remove 2>/dev/null, add -d)
+# 3: + trace on
+#
+# APT::Periodic::RandomSleep "1800";
+# - The apt cron job will delay its execution by a random
+# time span between zero and 'APT::Periodic::RandomSleep'
+# seconds.
+# This is done because otherwise everyone would access the
+# mirror servers at the same time and put them collectively
+# under very high strain.
+# You can set this to '0' if you are using a local mirror and
+# do not care about the load spikes.
+# Note that sleeping in the apt job will be delaying the
+# execution of all subsequent cron.daily jobs.