It's generated by syslogd, and is intended to show that logging is still active. You can use the "-m" option to change it's frequency.
On Mon, Dec 07, 1998 at 08:29:52PM +0100, Armin Wegner wrote: > Every twenty minutes my xconsole writes a string consisting of date > and time, my hostname and the string "-- MARK --". What does this > mean? This is new and I can't remember when it first happened and what > it caused to do so.
