Planning for code buffer management in distributed virtual execution environments

Abstract

Virtual execution environments have become increasingly useful in system implementation, with dynamic translation techniques being an important component for performance-critical systems. Many devices have exceptionally tight performance and memory constraints (e.g., smart cards and sensors in distributed systems), which require effective resource management. One approach to manage code memory is to download code partitions on-demand from a server and to cache the partitions in the resource-constrained device (client). However, due to the high cost of downloading code and re-translation, it is critical to intelligently manage the code buffer to minimize the overhead of code buffer misses. Yet, intelligent buffer management on the tightly constrained client can be too expensive. In this paper, we propose to move code buffer management to the server, where sophisticated schemes can be employed. We describe two schemes that use profiling information to direct the client in caching code partitions. One scheme is designed for workloads with stable run-time behavior, while the other scheme adapts its decisions for workloads with unstable behaviors. We evaluate and compare our schemes and show they perform well, compared to other approaches, with the adaptive scheme having the best performance overall.

Fragment cache management for dynamic binary translators in embedded systems with scratchpad

“…Although more sophisticated eviction policies are possible, flushing the F$ is a simple one that is used to minimize the overhead of managing the F$ [5,11,27]. The problem with this approach is that fragments which are soon needed can be evicted, especially for a small F$.…”

“…The management of the F$ has been widely studied for general-purpose systems and large fragment caches [2,3,4,5,11,21,23,27]. Bala et al suggested the strategy of flushing the F$ when it becomes full [2].…”

“…Zhou et al investigated F$ management for smartcards [27]. This work used a code server to download on-demand code into the F$.…”

“…DBT has led to new software capabilities, such as resource virtualization, intrusion detection, performance improvement, and instruction set migration. Although DBT has been widely applied to general-purpose systems, recent work has shown several uses of DBT for embedded systems, including power management [26], security [17,22], software caches [19], instruction set translation [6] and memory management [23,27].…”

Evaluating fragment construction policies for SDT systems

“…Strata has been used for a variety of applications including system call monitoring, dynamic download of code from a server, and enforcing security policies [12,25]. This section describes some of the basic features of Strata which are important to understanding the experiments presented later.…”