Ultraverse: A System-Centric Framework for Efficient What-If Analysis for Database-Intensive Web Applications

TL;DR

Ultraverse tackles the problem of enabling fast, correct what-if analysis for database-intensive applications by unifying application and database views. It uses dynamic symbolic execution to transpile each application-level transaction into a semantically equivalent SQL PROCEDURE, then replays targeted transactions with a novel retroactive DBMS plugin that leverages column-wise and row-wise dependency analyses and a Hash-Jumper for early termination. The approach yields substantial speedups (up to thousands of X against prior work) with modest overhead and supports unmodified DBMSs and legacy code. Its practical impact lies in enabling scalable, accurate retrospective analysis for complex, real-world workloads while preserving application semantics and transactional correctness. Ultraverse thus offers a comprehensive framework for system-centric what-if analysis that can influence decision-making in BI, operations, and software reliability tasks.

Abstract

Existing what-if analysis systems are predominantly tailored to operate on either only the application layer or only the database layer of software. This isolated approach limits their effectiveness in scenarios where intensive interaction between applications and database systems occurs. To address this gap, we introduce Ultraverse, a what-if analysis framework that seamlessly integrates both application and database layers. Ultraverse employs dynamic symbolic execution to effectively translate application code into compact SQL procedure representations, thereby synchronizing application semantics at both SQL and application levels during what-if replays. A novel aspect of Ultraverse is its use of advanced query dependency analysis, which serves two key purposes: (1) it eliminates the need to replay irrelevant transactions that do not influence the outcome, and (2) it facilitates parallel replay of mutually independent transactions, significantly enhancing the analysis efficiency. Ultraverse is applicable to existing unmodified database systems and legacy application codes. Our extensive evaluations of the framework have demonstrated remarkable improvements in what-if analysis speed, achieving performance gains ranging from 7.7x to 291x across diverse benchmarks.

Figures (17)

• Figure 1: An E-commerce web server's user request handler.
• Figure 2: The comprehensive architecture of Ultraverse.
• Figure 3: Augmented JavaScript code of \ref{['fig:new-follows-code']}.
• Figure 4: Transpiled SQLPROCEDURE version of \ref{['fig:new-follows-code']}.
• Figure 5: DSE's execution path tree of the "NewOrder" application-level transaction in \ref{['fig:new-follows-code']}.

Theorems & Definitions (17)

• Definition 1: Retroactive Operation
• Definition 2: Read/Write Set
• Definition 3: Query Dependency
• Proposition 1
• Proposition 2
• Definition 4: $\mathbb{I}$
• Proposition 3
• Definition 5: Read-then-Writer
• Proposition 4
• Proposition 5