RankReclaim: Counting the Capacity an Edited Layer Has Actually Spent

Lifelong model editing corrects a deployed model many times, and each correction arrives as a low-rank update to one layer of fixed width, the resource every later correction draws on. Editors decide when the layer is full by summing the ranks the corrections request, yet corrections share input directions: on one stream the requested total reaches $48$ by the eighteenth arrival while only $30$ directions are committed, and the consolidations that return width are executed before their cost to earlier corrections is read. We propose RankReclaim, which counts the directions a layer has actually committed instead of summing requested ranks, and prices every consolidation before it executes. A committed-capacity ledger reads the numerical rank of the stacked input factors and attributes to each correction the directions its removal would return, testing admission against the measured count. Priced reclamation evaluates a candidate truncation on the stored probes of every surviving correction and executes it only at the smallest rank whose accumulated displacement stays inside a tolerance, quoting the cost of returned width before it is paid. Overlap-budgeted placement splits each arrival's fit against the committed span and caps the share drawn from the free width, holding every arrival's draw at or under a set budget. The three components share one committed basis per layer and act on the one count the ledger produces. On three edit streams run to three times the per-layer budget, the requested-rank account serves $6$, $7$ and $6$ corrections, the measured count alone $9$, $8$ and $13$ at zero displacement, and RankReclaim $13$, $15$ and $15$. Among eight arms, RankReclaim is the only reclaiming arm that holds the committed count at the budget, $16$, $15$ and $16$ of $16$, and the only one that reads the displacement of every consolidation before executing it, returning width at $26\%$ to $36\%$ of the displacement of a fixed-rank consolidation.