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Re: ISSUE-826 Re: More Problems with Preemption

From: chris nuernberger <cnuernber@gmail.com>
Date: Fri, 8 Feb 2013 08:28:19 -0700
Message-ID: <CAG=GWvdKpLuhFM0Z3OH6RCZPEsY8Yv5VhAXiYTe3N7x0o+efPw@mail.gmail.com>
To: Jim Barnett <Jim.Barnett@genesyslab.com>
Cc: "www-voice@w3.org" <www-voice@w3.org>
Actually, I think there is one solid difference not take into account by
your algorithm.

The algorithm I proposed will correctly preempt any targetless transitions
in exit set.  Your algorithm will not without modification.

Chris


On Fri, Feb 8, 2013 at 8:13 AM, chris nuernberger <cnuernber@gmail.com>wrote:

> OK, I can buy that although I do think it is odd to propose an algorithm
> that is demonstrably less efficient.  I guess I just find this definition
> much clearer:
>
> Arena Orthogonal : Two transition occurrences are included in the same
> small-step only if their arenas are orthogonal, where the arena of a
> transition is the smallest (lowest in the hierarchy of the composition
> tree) Or-state that is the (grand)parent of the source and destination
> control states of the transition.
>
> Obviously that would be the transition arena would be defined by the
> transition subgraph root.
>
> This is also the definition used in the white paper linked to from SCION's
> comparison page.
>
> Is it possible that transactions with non-conflicting exit sets would have
> conflicting entry sets?
>
> Chris
>
>
> On Fri, Feb 8, 2013 at 8:07 AM, Jim Barnett <Jim.Barnett@genesyslab.com>wrote:
>
>>  Speed is not an issue in the algorithm, since implementations are only
>> required to behave _*as if*_ they are implementing the algorithm in the
>> spec.  There are all sorts of places where the spec algorithm can be
>> optimized (it calculates certain values over and over again, instead of
>> caching them.  And you wouldn’t bother with  filterPreempted at all if you
>> only had a single transition.)****
>>
>> ** **
>>
>> I think that the advantage of the version that I proposed is that it is
>> very close to the normative wording of the spec, which is in turn taken
>> from UML, with which we try to stay consistent.  ****
>>
>> ** **
>>
>> **-          **Jim****
>>
>> ** **
>>
>> *From:* chris nuernberger [mailto:cnuernber@gmail.com]
>> *Sent:* Friday, February 08, 2013 10:02 AM
>> *To:* Jim Barnett
>> *Cc:* www-voice@w3.org
>> *Subject:* Re: ISSUE-826 Re: More Problems with Preemption****
>>
>> ** **
>>
>> In which cases would this algorithm differ from the one I proposed?  ****
>>
>> ** **
>>
>> The one I proposed is far faster.****
>>
>> ** **
>>
>> Chris****
>>
>
>
>
> --
> A foolish consistency is the hobgoblin of little minds - Emerson
>



-- 
A foolish consistency is the hobgoblin of little minds - Emerson
Received on Friday, 8 February 2013 15:28:46 GMT

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