Faster BlockMax WAND with Variable-sized Blocks
Antonio Mallia, Giuseppe Ottaviano, Elia Porciani, Nicola Tonellotto, Rossano Venturini · 2017
Query processing is one of the main bottlenecks in large-scale search engines. Retrieving the top k most relevant documents for a given query can be extremely expensive, as it involves scoring large amounts of documents. Several dynamic pruning techniques have been introduced in the literature to tackle this problem, such as BlockMaxWAND, which splits the inverted index into constant- sized blocks and stores the maximum document-term scores per block; this information can be used during query execution to safely skip low-score documents, producing many-fold speedups over exhaustive methods.