Under the Hood: Elasticsearch 8.15's Search Index vs. OpenSearch 2.12's Fork for Log Aggregation Log aggregation remains a critical workload for engineering teams, with Elasticsearch and OpenSearch dominating the ecosystem. Elasticsearch 8.15 and OpenSearch 2.12 represent two diverging paths: the former a commercially backed, rapidly evolving search platform, the latter a fully open-source fork of Elasticsearch 7.10. This deep dive compares their core search index architectures and performance for log aggregation workloads. Background: Divergence in the Ecosystem OpenSearch forked from Elasticsearch 7.10 in 2021 following licensing changes to Elasticsearch. Both tools rely on Apache Lucene as their underlying search library, but have since added independent features, optimizations, and Lucene version upgrades.…