Last-use opacity: a strong safety property for transactional memory with prerelease support

Abstract Transaction Memory (TM) is a concurrency control abstraction that allows the programmer to specify blocks of code be executed atomically as transactions. However, since transactional can contain just about any operation attention must paid state shared variables at given time. E.g., contrary database transaction, if TM transaction reads stale value it may execute dangerous operations, like attempt divide by zero, access an illegal memory address, or enter infinite loop. Thus serializability insufficient, and stronger safety properties are required in TM, which regulate what values read, even transactions abort. Hence, number were developed, including opacity, TMS1 TMS2. such strong preclude using prerelease technique for optimizing because they virtually forbid reading from live On other hand, do allow either not enough prevent problems mentioned above (recoverability), add additional conditions on limit their applicability (elastic virtual world consistency). This paper introduces last-use opacity pair new meant compromise between minimal ones serializability. The eliminate all but small class benign inconsistent views pose no stringent