Protecting Private Data in the Cloud

Companies that process business critical and secret data are reluctant to use utility and cloud computing for the risk that their data gets stolen by rogue system administrators at the hosting company. We describe a system organization that prevents host administrators from directly accessing or installing eaves-dropping software on the machine that holds the client's valuable data. Clients are monitored via machine code probes that are inlined into the clients' programs at runtime. The system enables the cloud provider to install and remove software probes into the machine code without stopping the client's program, and it prevents the provider from installing probes not granted by the client

The economics of garbage collection

This paper argues that economic theory can improve our understanding of memory management. We introduce the allocation curve, as an analogue of the demand curve from microeconomics. An allocation curve for a program characterises how the amount of garbage collection activity required during its execution varies in relation to the heap size associated with that program. The standard treatment of microeconomic demand curves (shifts and elasticity) can be applied directly and intuitively to our new allocation curves. As an application of this new theory, we show how allocation elasticity can be used to control the heap growth rate for variable sized heaps in Jikes RVM

Actors that Unify Threads and Events

There is an impedance mismatch between message-passing concurrency and virtual machines, such as the JVM. VMs usually map their threads to heavyweight OS processes. Without a lightweight process abstraction, users are often forced to write parts of concurrent applications in an event-driven style which obscures control flow, and increases the burden on the programmer. In this paper we show how thread-based and event-based programming can be unified under a single actor abstraction. Using advanced abstraction mechanisms of the Scala programming language, we implemented our approach on unmodified JVMs. Our programming model integrates well with the threading model of the underlying VM

Secure Virtualization and Multicore Platforms State-of-the-Art report

SVaM