The document discusses how Box is scaling its search capabilities to handle a petabyte-scale index. It outlines Box's existing search infrastructure and scaling issues, and proposes solutions like key range partitioning, shard growth handling, and optimized shard allocation to improve query performance and cluster utilization as the index grows towards 1 petabyte in size over the next 5 years. The talk also covers future work like integrating key range partitioning into SolrCloud and building a search federation service to classify and rank results across collections.