Remote memory transfers (RMTs) allow processors to access non-local memories without involving the remote processor. As the only interprocessor synchronization required is setting flags on the local and remote processors after the tranfer is complete, RMTs do not ential the overhead due to the handshaking and buffering of message passing nor require the complex hardware of cache-coherent shared memory. The minimal synchronization of RMTs, however, necessiates extra remote communications to enforce common data sharing paradigms, such as producer/consumer. We propose a new hardware mechanism: the conditional RMT (CMRT). CRMTs succeed or fail depending on the state of the remote data. We describe potential CRMT hardware definitions, and illustrate their utility by presenting efficient software protocols for producer/consumer and check-in/check-out data sharing.
By: Susan Flynn Hummel
Published in: RC20113 in 1995
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