Top Document: Comp.os.research: Frequently answered questions [3/3: l/m 13 Aug 1996] Previous Document: [1.5.1.2] Relaxing consistency Next Document: [1.5.2] Access synchronisation See reader questions & answers on this topic! - Help others by sharing your knowledge From: Distributed systems From [Cheriton, 86]: `Problem-oriented shared memory' is a shared memory that implements fetch and store operations specialised to the particular problem or application it is supporting. In particular, a problem-oriented shared memory commonly provides a specialised form of consistency and consistency maintenance that exploits application-specific semantics. Cheriton goes on to propose that consistency constraints be relaxed and more use be made of problem semantics. He suggests that, in some cases, stale data may be detected on use by the client, and the client may then recover. A example would be hint caching. In some applications, stale data may actually be sufficiently accurate, provided that the client can obtain up to date information when necessary. In other applications, some data may be optional in the sense that the client can continue without it. Other applications may tolerate having the results of store operations being lost or undone, for example, an application that regularly updates the entire data set. Another approach is presented by the designers of Munin, where the runtime system accepts hints from the compiler or user to determine the coherence mechanism to be used for each object. The default, in the absence of hints, is to use a general read-write consistency mechanism, much like that employed by IVY. Munin supports several different object types that are based on the results of a survey of shared memory access characteristics. The results of the survey showed that a very small percentage of all accesses to shared data fall under the general read-write type. The Munin designers also note that a program moves through various stages of execution, and the types associated with objects change as time progresses User Contributions: 1 UoowNen ⚠ Sep 24, 2021 @ 7:07 am buy zithromax online https://zithromaxazitromycin.com/ - buy zithromax online zithromax online https://zithromaxazitromycin.com/ - buy zithromax Comment about this article, ask questions, or add new information about this topic:Top Document: Comp.os.research: Frequently answered questions [3/3: l/m 13 Aug 1996] Previous Document: [1.5.1.2] Relaxing consistency Next Document: [1.5.2] Access synchronisation Part1 - Part2 - Part3 - Single Page [ Usenet FAQs | Web FAQs | Documents | RFC Index ] Send corrections/additions to the FAQ Maintainer: os-faq@cse.ucsc.edu
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