The Fermi-LAT tracker has been operating reliably for the last four years as configured at launch in June 2008. We report on an initiative to modify the readout configuration of the tracker to yield more complete data for events with a large number of hits. The tracker readout is hierarchical: read controllers (GTRCs) collect hits from each plane of the tracker, and cable controllers (GTCCs) collect the GTRC hits, from the bottom up, for assembly into the event to be read out. The GTRCs and the GTCCs can buffer a limited number of hits; at the outset we chose the maximum hit count in the GTRCs to be the same in all the planes, and small enough to guarantee that the GTCC buffers would never fill completely.
This turns out not to be optimal, especially for high-energy photons. The goal of the present effort is to allow for more hits at the bottom of the tracker, where the photon-induced electromagnetic shower is fullest, while losing few (if any) hits at the top, to the extent allowed by the hardware. We present the rationale for the change and the results of engineering runs and Monte Carlo simulations to test a particular implementation, chosen to produce minimal disruption of ongoing science analyses.