Hermes: Off-the-Shelf Real-Time Transactional Analytics

Many modern applications require real-time analytics, where analytical processing (AP) workloads needs access to the latest data updates from a transactional processing (TP) engine. However, managing separate TP and AP engines across teams complicates achieving real-time analytics without switching to specialized HTAP systems. To address this challenge, we introduce off-the-shelf real-time analytics , a system design that leverages the existing TP and AP engines to provide (1) the latest transactional updates for analytical queries and (2) support for efficient transactional analytics-transactions that combine transactional logic and analytical queries within a single ACID transaction-at various isolation levels. We demonstrate this concept with a new service called Hermes , which acts as a middleware that merges log records with analytical reads without altering existing engines. Our evaluation utilizes two AP engines, FlexPushdownDB and DuckDB , with MySQL as the TP engine. Using the HATtrick benchmark and a new workload called Transactional Analytics Workload (TAW), we compare Hermes with the leading HTAP solution, TiDB. Our results indicate that Hermes performs comparably to current HTAP solutions for real-time analytics and surpasses them by 3× in transactional analytics performance.