SynRGen: an extensible file reference generator

SynRGen, a synthetic file reference generator operating at the system call level, is capable of modeling a wide variety of usage environments. It achieves realism through trace-inspired micromodels and flexibility by combining these micromodels stochastically. A micromodel is a parameterized piece of code that captures the distinctive signature of an application. We have used SynRGen extensively for stress testing the Coda File System. We have also performed a controlled experiment that demonstrates SynRGen's ability to closely emulate real users—within 20% of many key system variables. In this paper we present the rationale, detailed design, and evaluation of SynRGen, and mention its applicability to broader uses such as performance evaluation.