How a Two-Decade-Old Issue Still Haunts Software Scalability by Luca Molteni and Francesco Nigro

Time-Traveling Bugs: How a Two-Decade-Old Issue Still Haunts Software Scalability In this session, we will explore how seemingly insignificant and often overlooked details in our code can significantly impact software performance, especially regarding concurrency. A two-decade-old JVM bug, initially discovered within Quarkus, is not a concern limited solely to low-level programmers; instead, it is a potential issue that could affect any codebase. We will provide a comprehensive explanation of this problem, detailing how we identified and successfully addressed it in Drools, one of the most widely-used rule engines in the Java ecosystem. We will also introduce specific tools that every developer can employ to enhance their code's performance. Lastly, we’ll analyze the new features of Java 21 to see if they’re affected by the same problem.