On 07/07/2011 10:25, Efthymia Tsamoura wrote: > Hello Hello
[snip of interesting service-invocation ordering] > It would be very useful to know if there exist similar scientific > workflow examples (where the order of task invocation can change and > it is not known a-priori by the user, while the workflow performance > depends on the workflow task invocation order) There are certainly problems where different ordering of the services (or very similar services) can still achieve the same result but have very different performace. I know that for some bioinformatics workflows pre-filtering ids before you query a database can have a huge impact on performance. I'm not sure what you mean by "the order of task invocation can change and it is not known a-priori by the user". For a specific workflow, services in Taverna are invoked as soon as the data is available (apart from some special cases). It depends on the workflow as to whether you can tell which order the services are invoked in. Basically, if the workflow branches then you cannot normally predict the relative order of service invocation in the different branches. If you are asking if there are times when users cannot decide which order to put the services in the workflow, then there are almost certainly such cases. > and if you are > interested in extending taverna with optimization algorithms for such > workflows. It sounds interesting. Are you thinking of dynamically altering the order during an actual workflow run, or does this happen during workflow design? Even if you managed to just warn that a workflow was inefficient it would help a lot. How do you model the semantics of the services? > I am asking because i have recently developed an optimization > algorithm for this problem and i would like to test its performance in > a real-world workflow management system with real-world workflows. I think it is best to copy your question to the Taverna users' mailing list as the subscribers may be able to point you at particular workflows. Have you looked at http://www.myexperiment.org to see if there are any relatively simple workflows that you can test on? > P.S.: references to publications or any other information dealing with > scientific workflows of the above rationale will be extremely useful. The one that I am most familiar with is the work done on the eLico project for generating optimized data mining workflows. It is at http://www.e-lico.eu/?q=DMOP > Thank you very much for your time Alan ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 _______________________________________________ taverna-hackers mailing list [email protected] Web site: http://www.taverna.org.uk Mailing lists: http://www.taverna.org.uk/about/contact-us/ Developers Guide: http://www.taverna.org.uk/developers/
