Abstract: An asynchronous parallel simulation protocol useful to simulate events in a stream processing platform. The invention is a windowing scheme which is suitable for distributed stream computing platforms containing facilities for supporting fully asynchronous processing elements and downstream event flows. It is a realization of the concept of a BSP superstep based oracle simulator that enables using statistics from the recent past to conduct the actual optimistic simulation at low rate of straggler messages. The invention is capable of achieving good statistic agreement with results from sequential simulations of the same models.

Abstract: A prediction method for estimating the running time of WAND queries executed on a Web search engine which includes an off-line component using the Discrete Fourier Transform to models the index as a collection of signals to obtain characteristic vectors for query terms and an on-line feed-forward neural network with back-propagation to estimate the time required to process the incoming queries. The DFT is used to obtain values for six characteristics of the posting lists associated with the query terms. These characteristics are used to train a neuronal network which is used to predict the query execution time.

Abstract: A search engine is operated to handle a plurality of queries. In particular, in response to each of the plurality of queries presented to the search engine, the search engine provides an indication of at least one document responsive to that query. An indication is determined of an amount of resources of the search engine to handle a subset of the plurality of queries. Based on the determined indication, the search engine is selected to operate in one of a synchronous mode and an asynchronous mode, and the search engine is operated in accordance with the selected mode.

Abstract: The subject matter disclosed herein relates to forming a computer generated distributed index data structure.

Abstract: A search engine is operated to handle a plurality of queries. In particular, in response to each of the plurality of queries presented to the search engine, the search engine provides an indication of at least one document responsive to that query. An indication is determined of an amount of resources of the search engine to handle a subset of the plurality of queries. Based on the determined indication, the search engine is selected to operate in one of a synchronous mode and an asynchronous mode, and the search engine is operated in accordance with the selected mode.