Server performance has always been an active field of research, spanning topics including databases, network applications, and cloud computing. Tail latency is one of the most important performance metrics for server performance. In this work, we study how different timing components affect server workload performance, including thread contention and interrupt handling. We introduce a workload analysis and generation tool: TailWAG. TailWAG relies on measured timing components from applications to generate a synthetic workload that mimics the original behavior. TailWAG can help server designers and application developers explore performance bottlenecks and optimization opportunities at early stages.