Sane Semantics of Best-effort Hardware Transactional Memory
نویسندگان
چکیده
Transactional memory’s (TM) biggest promise is that of making it easier to devise scalable multi-core programs. Arguably the biggest simplification of reasoning about parallel code with TM comes from atomicity : transactions either take effect instantaneously, or not at all. TM frees the programmer from reasoning how this atomicity is achieved and asks only where it should be employed. Commercial proposals and implementations of hardware TM, such as Sun’s Rock [2] and AMD’s ASF [1], face a number of limitations and also propose extensions to the all-or-nothing semantics of TM, essentially permitting a set of visible side-effects on various levels. In this abstract (and talk), we will outline several spots of weakened semantics, discuss implications for applications through some examples, and provide a solution within our ASF framework. Because this is work in progress, we would like to discuss whether our specification is useful and whether it is sufficiently detailed and clear.
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