User talk:Zha Ewry/AWG: Desiderata for evaluating the proposed design

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Revision as of 04:19, 27 September 2007 by Morgaine Dinova (talk | contribs)
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Plug and proxy models

It's worth mentioning that the matter of proxies (and caches, which are strongly related) is very important on the distribution/scalability front as well. When a private world machine or small external grid attaches to a large enterprise grid like that of LL, the influx of visitors from large to small would almost always overwhelm the small site in the absence of a proxy and caching mechanism within the large site, as a natural consequence of their relative scales.

Consequently, the concept of proxy needs to be expanded substantially for a scalable distributed world system, ie. to cache external state and to handle much of the object-related traffic that would otherwise all be funnelled out to the small system on every access. Without this, large systems will never be able to connect to small ones in a manner that would satisfy their residents, because the small systems would always be "Slashdotted", to coin a phrase. --Morgaine Dinova 03:34, 24 September 2007 (PDT)

Although each attached grid would naturally be authoritative for its own contained objects, the degree of passthrough of object transactions needs to be a tunable parameter to cater for the disparity in sizes. For example a world on a laptop might receive transactions at only 1/1000th the rate at which its objects held within the caching proxy are accessed on the large grid to which it is attached. A rough analogy with the DNS system and also with transparent web proxies might help visualize the kind of relationships required in this area for scalability in a distributed system. --Morgaine Dinova 03:52, 24 September 2007 (PDT)