CAPMA: a content-addressable pattern match architecture for production systems

CAPMA is an efficient partially parallel pattern match architecture used to speed up the execution time of match process of a production system. The algorithm fully exploits the advantages of content-addressable memories (CAMs) not only to buffer the working memory elements, but also to support the functions for evaluating interconditions among patterns in the left-hand sides (LHSs) of productions. CAPMA compiles the LHS of each production into an efficient form, and creates an effective accessing mechanism based on a two-level CAM architecture for computing the conflict set. Both upper-level and lower-level CAM arrays give CAPMA two major benefits: (i) embedded parallelism of pattern matching at the speed of nano-seconds, and (ii) uniformity to construct arrays of processing elements for matching. Due to the modifiability nature of CAMs, knowledge in production systems can be easily added, deleted or modified in CAPMA. CAPMA also grainy simplifies the maintenance efforts and control actions needed by the working memory (WM). Preliminary timing simulations indicate that approximately 8000 match cycles per second can be performed with 20 MHz CAMs