- From: Drew McDermott <drew.mcdermott@yale.edu>
- Date: Mon, 4 Oct 2004 02:34:35 +0000 (GMT)
- To: public-sws-ig@w3.org
This is a response to a note by Naveen Srinivasan in another venue, reposted here with this permission -- > From: Naveen Srinivasan <naveen@cs.cmu.edu> > > Based on our telecon discussion here is an example for unorder construct > > Let us consider a composite process composed of 10 different smaller > processes, and each smaller process purchases an item. Let each of the > smaller process's process model consist of three parts, first > withholding $200 from the user's credit card, followed by actual > purchase (for simplicity let us assume that item's cost is less than > $200) and finally release the remaining of the $200 previously withheld. > > Since there are no dependencies (atleast I/O wise) between the smaller > process, one can choose to model the above composite process as split or > split-join. Let us assume that the user's credit limit is $500 and the > total cost of all the 10 articles he is about to purchase is $75. In > this case both split and split-join will not succeed, because each of > the 10 process will try to block $200 and some process may fail. > > On the other hand an Unorder process (based on Drew's definition) will > not fail because Unorder construct will not execute all the processes > concurrently rather executes them in no particular order. I have always assumed that "unordered" meant that composite processes could be interleaved. Your interpretation seems to imply that the unordered combination of process P_1,...,P_k is eqivalent to a random ordered permutation of the P_i. Have I misunderstood? -- Drew -- -- Drew McDermott Yale CS Department
Received on Monday, 4 October 2004 02:35:07 UTC