The CDF Run II silicon detector with its 8 layers of double- and
single-sided silicon microstrip sensors and a total 722,432 readout channels
is one of the largest silicon detector devices currently in use by a HEP
experiment.  We report our experience commissioning and operating this
complex device during the first 4 years of Run II.  As the luminosity
delivered by the Tevatron increases, we have observed measurable effects of
radiation damage in studies of charge collection and noise versus applied
bias voltage at many different integrated luminosities.  We discuss these
studies and their impact on the expected lifetime of the detector.