Highly E cient and Encapsulated Re-use of Synchronization Code in Concurrent Object-Oriented Languages

Re-use of synchronization code in concurrent OOlanguages has been considered di cult due to inheritance anomaly, which we minimize with our new proposal. Designed with high practicality in mind, we propose language primitives (plus their implementation) with the following characteristics: (1) it allows multiple synchronization schemes|the language schemes for programming synchronization|to coexist and be integrated, (2) re-use of synchronization code is done similarly to sequential OO-languages for user familiarity, (3) it o ers high degree of encapsulation|even synchronization schemes could be encapsulated in superclasses in many cases, and (4) it can be e ciently implemented on conventional MPPs. We demonstrate the e ectiveness of our proposal with solutions to the example inheritance anomaly cases from [16]. We also give an overview of the implementation architecture, along with preliminary benchmarks. The proposed language primitives are being incorporated into our ABCL/onAP1000 running on Fujitsu's 512-node MPP, AP1000.