- From: Kohei Honda <kohei@dcs.qmul.ac.uk>
- Date: Wed, 20 Jul 2005 15:21:27 +0100
- To: Monica J Martin <Monica.Martin@Sun.COM>
- CC: public-ws-chor@w3.org, yoshida@doc.ic.ac.uk
Dear Monica, My apologies that I was very late in my reply. Monica J Martin wrote: > Kohei, A brief question (or clarification for me): see inline. > >> (1) Two versions of the text. >> >> (1-1) version 1 (without must). >> >> Distinct instances of a (top-level or enclosed) choreography, if >> they ever run in a temporarily overlapped fashion, are not assumed >> to interfere with each other in their involved communication >> actions. In other words, given a choreography description, >> interactions belonging to one of its instances are assumed to be >> logically, hence executionally, distinguishable from those in >> another. >> >> (1-2) version 2 (with must). >> >> Distinct instances of a (top-level or enclosed) choreography, if >> they ever run in a temporarily overlapped fashion, must not >> interfere with each other in their involved communication actions. >> In other words, given a choreography description, interactions >> belonging to one of its instances must be logically, hence >> executionally, distinguishable from those in another. >> >> (2) Comments. >> >> Terminology: I used the term "instance". I am not sure this term >> can be used for denoting a run of a top-level choreography (the >> attribute name "choreographyInstanceId" seems to be used only for >> enclosed choreographies). We can use the term "runs" instead of >> "instances". I also used "temporarily ovelapped" instead of "in >> parallel" or in "concurrent" to be concrete about what is meant. >> > mm1: Kohei, can you differentiate / explain why you don't use parallel > or concurrent, as opposed to temporarily overlapped. And, what is the > intent in what behavior we expect and wish to manage. Thanks. > There are many ways people define "concurrency" and "parallelism". In this instance I would personally use the term "concurrent" (which means, to me, there are logically several threads of activities going on), but to be non-ambiguous I used "temporarily overlapped". However I am glad it is changed into "concurrent". In fact "temporarily overlapped" can also be misleading since it may connote they should physically be runnig in parallel. This is not what I meant: they can be run on the same single CPU machine as two or more logical units. In this case "in a temporarily overlapped fasion" becomes "concurrently" or "concurrently, for example in different threads or processes". Best wishes, kohei
Received on Wednesday, 20 July 2005 14:21:35 UTC