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Next great article from Google: Percolator. The whitepaper describes a new indexing engine, which no longer uses the massive MapReduce algorithm to calculate web pages indexes. As always, Google used a few already existin g tools, like BigTable and build an index updater, which opposite to MapReduce updates small chunks of the index repository drastically reducing :-) the time between a page being crawled and being indexed. Worth to read, even for the transaction scheme implemented on the non-transactional BigTable.
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