Java application servers are gaining popularity as a way for businesses to conduct day-to-day operations. While strong emphasis has been placed on how to obtain peak performance, only a few research efforts have focused on these servers' ability to sustain top performance in spite of the ever-changing demands from users. As a preliminary study, we conducted an experiment to observe the throughput degradation behavior of a widely-used Java application server running a standardized benchmark and found that throughput performance degrades ungracefully. Thus, the goal of this work is three-fold: (i) to identify the primary factors that cause poor throughput degradation, (ii) to investigate how these factors affect throughput degradation, and (iii) to observe how changes in algorithms and policies governing these factors affect throughput degradation. Key words: Application servers, throughput degradation, garbage collection, performance analysis