Instrumentation in software dynamic translators for self-managed systems

Abstract

Self-managed software requires monitoring and code changes to an executing program. One technology that enables such self management is software dynamic translation (SDT), which allows a program's execution to be intercepted and controlled by a separate software layer. SDT has been used to build many useful applications, including software security checkers that check for code vulnerabilities, dynamic code optimizers, and program introspection tools. While these systems use program instrumentation, the instrumentation is usually tailored to a specific application and infrastructure. What is missing is a single scalable and flexible instrumentation framework that can be used in different self-managed SDT infrastructures. In this paper, we describe such a framework, called "FIST," that can be used and targeted by different algorithms and tools to enable instrumentation applications that are portable across SDTs and machine platforms. Our interface supports multiple levels of granularity from source level constructs to the instruction and machine level. We describe and evaluate FIST's capabilities in the Strata system for the SPARC and the Jikes Research Virtual Machine for Java on the Intel x86.