Re: Pattern for One-Entry-Multiple-Workers Problem

Stefan Schulz wrote:
> John McClain - Sun Microsystems, Inc. wrote:
>
>> Stefan Schulz wrote:
>>
>>> In the end, there is still the alternative to (externally) trigger a
>>> contents()/iterator-base operation, as mentioned by Gregg. Although, not
>>> very elegant, maybe the easiest and most complete way to do it. Hm.
>>
>>
>> Just so I can understand, can you write about why you consider
>> a contents based solution "inelegant"?
>
>
> It's non-elegant in my scenario, as each worker would have to touch all
> matching entries instead of only the one(s) yet unprocessed by him.
>
> In a scenario, where only one result is expected, a worker could react
> upon receiving a notification, (try to) take the entry and either
> "replace" the entry with the result entry or "mark" the entry to be
> processed. Hence, each requesting entry only is read once by a worker.
>
> In my scenario, however, multiple independent results of an undetermined
> number are expected as response to one requesting entry. Using
> contents(), each worker has to read such entries multiple times, as they
> do not get "consumed", until the requesting manager decides to.
>
> I think, the Call for Papers-Example makes it easier to understand:
> you can either ask your students to read all the CfPs kept as unordered
> stack on the secretaries desk regularily, triggered by an email stating
> that "a new CfP has arrived", or you send a new CfP (as a copy and
> notification in once) to each of them.
>
> I learned that the latter obviously is possible by using availability
> notifications in JavaSpace05. To guarantee a worker seeing all
> requesting entries, however, the contents() method would still have to
> be applied. Hence, the contents() approach seems more complete.

Just so I can nail this down in my head, do you view the "contents +
availability event" approach inelegant too? Or is your elegants issue
only with using contents w/o the availability event?

What rate are the your "CfPs" being generated at? Are they being
generated by one entity or many? How much time does it take respond to a
CfP? How many responses do you expect to get from a single CfP?

--
BTW, if you want to reply to this message, please direct your reply
to the list, thanks

John McClain                                    [email protected]
Sun Microsystems, Inc.
Burlington, MA

A business that makes nothing but money, is a poor business.
    - Henry Ford

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