  The synthetic workload is essential and critical to the performance
evaluation of database systems. When evaluating the database performance for a
specific application, the similarity between synthetic workload and real
application workload determines the credibility of evaluation results. However,
the workload currently used for performance evaluation is difficult to have the
same workload characteristics as the target application, which leads to
inaccurate evaluation results. To address this problem, we propose a workload
duplicator (Lauca) that can generate synthetic workloads with highly similar
performance metrics for specific applications. To the best of our knowledge,
Lauca is the first application-oriented transactional workload generator. By
carefully studying the application-oriented synthetic workload generation
problem, we present the key workload characteristics (transaction logic and
data access distribution) of online transaction processing (OLTP) applications,
and propose novel workload characterization and generation algorithms, which
guarantee the high fidelity of synthetic workloads. We conduct extensive
experiments using workloads from TPC-C, SmallBank and micro benchmarks on both
MySQL and PostgreSQL databases, and experimental results show that Lauca
consistently generates high-quality synthetic workloads.
