Practical Tips for Improving the Performance of Legacy Enterprise Applications

Hi everyone, I’m interested in learning how other developers and administrators approach performance optimization when working with long-running enterprise applications and legacy systems. In environments where applications have been running for many years, performance issues can sometimes come from several areas at once, such as database access, inefficient queries, application logic, memory usage, or system configuration. A few things I’d be interested to hear from the community: What performance issues do you encounter most frequently?