Elasticsearch 6.0 introduces significant improvements aimed at reducing index storage size, notably through the deprecation of the "all" field and enhancements in handling sparsely populated fields. The removal of the "all" field, which previously concatenated all values for easier searchability but consumed considerable storage due to data duplication, accounts for nearly 40% of the storage savings. The remaining 60% is attributed to updates in Lucene 7.0, which accompanies Elasticsearch 6.0, allowing for more efficient storage of sparse fields by using an iterator-based approach to avoid storing empty values, thus reclaiming extra storage space. These changes, requiring minimal user intervention beyond an upgrade, result in a 41.5% reduction in storage space when tested with Metricbeat, a tool that frequently deals with sparsely populated fields.