IOLM-DB: Instance-optimized large language model execution for column-scale semantic operators

Large language models (LLMs) can implement row-level semantic transformations over tabular data, but a general-purpose model reserves the same accelerator resources even when every row uses one fixed prompt. IOLM-DB compiles that recurring prompt–column pair into an operator sized to the work it actually does. It samples the target column, constructs calibration sequences that represent both prompt and output behavior, evaluates specialized candidates, and selects an implementation under explicit memory and quality constraints. Across heterogeneous datasets and operator types, column-calibrated quantization reduces the resident footprint of the reference model by 1.8–2.8 × while the 8-bit profile remains a near-lossless replacement and the 4-bit profile preserves behavior on categorical label-output operators. At fixed precision, column calibration consistently improves fidelity over generic GPTQ calibration, and output-aware calibration provides an additional benefit for generative operators. Deployment experiments reveal two complementary outcomes: weight-only compression does not raise per-row throughput in a compute-rich regime, where it primarily releases capacity, but the smaller weight stream also improves throughput when memory bandwidth becomes limiting. The compact artifacts enable deployment under a memory budget where the full-precision operator cannot start and allow three specialized operators to occupy roughly the footprint of one full-precision model. IOLM-DB therefore turns a recurring semantic transformation from an immutable call to a general-purpose backend into a compact, measurable, and hardware-aware operator.