Multithreaded programs are hard to get right. A key reason is that the contract between developers and runtimes grants exponentially many schedules to the runtimes. Two approaches improve correctness by reducing schedules. Deterministic multithreading (DMT) reduces schedules for each input down to one. Stable multithreading (SMT) reduces schedules for all inputs, increasing coverage of checking...

Technical systems are so powerful that there is a temptation to try to provide ‘perfect’ support for any cooperative work practice. Some CSCW problems result from designs motivated by optimising technical criteria. A very high bandwidth network, for instance, can support a wide variety of work patterns; the consequent focus of solving the salient technical problems gives the impression that CSC...

We address the goal of making Delegation Logic (DL) into a practically implementable and tractable trustmanagement system. DL [22] is a logic-based knowledge representation (i.e., language) for authorization in largescale, open, distributed systems. As introduced in [22], DL inferencing is computationally intractable and highly impractical to implement. We introduce a new version of Delegation ...