We describe and argue for a strategy of performance profiling and comparison in the engineering of parsing systems for wide-coverage linguistic grammars. A performance profile
is a precise, rich and structured snapshot of system (and grammar) behaviour at a given
development point. The aim is to characterize system performance at a very detailed
technical level, but at the same time to abstract away from idiosyncracies of particular
processors. Profiles are obtained with minimal effort by applying a specialized profiling
tool to a set of structured reference data (taken from both existing test suites and corpora),
in conjunction with a uniform format for test data and processing results. The resulting
profiles can be analyzed and visualized at various levels of granularity in order to highlight
different aspects of system performance, thus providing a solid empirical basis for system
refinement and optimization. Since profiles are stored in a database, comparison with
earlier versions, different parameter settings, or other processing systems is straightforward. We apply several salient performance metrics in a contrastive discussion of various
(one-pass, bottom-up, chart-based) parsing strategies (viz. passive vs. active and uni- vs.
bidirectional approaches). Based on insights gained from detailed performance profiles,
we outline and evaluate a novel ‘hyper-active’ parsing strategy. We also present preliminary profiles for techniques for ‘packing’ of local ambiguities with respect to (partial)
subsumption of feature structures.