Kernel Plugins: When a VM Is Too Much

This paper presents kernel plugins, a framework for dynamic kernel specialization inspired by ideas borrowed from virtualization research. Plugins can be created and updated inexpensively on-the-fly and they can execute arbitrary user-supplied functions such that neither safety nor performance are compromised. Three key techniques are used to implement kernel plugins: (1) hardware fault isolation, (2) dynamic code generation, and (3) dynamic linking. Hardware fault isolation protects kernel-level services from plugin misbehavior, dynamic code generation enables rapid online creation of arbitrary plugins, and dynamic linking governs the kernel/plugin interface. We discuss the design and implementation of the kernel plugin facility, as well as its advantages and shortcomings. Its use is demonstrated by a range of microand macro-benchmarks and a real-life application featuring plugins that dynamically transcode images served by a high-performance kernel web server. Benefits realized from...

• Type: Conference
• Year: 2004
• Where: JVM
• Authors: Ivan B. Ganev, Greg Eisenhauer, Karsten Schwan
• Keywords: Dynamic Code Generation, Education, Hardware Fault Isolation, JVM 2004, Kernel Plugin