Also see http://taverna.knowledgeblog.org/2010/12/13/iteration-in-taverna-workflows/ in http://www.mygrid.org.uk/dev/wiki/display/taverna/Implicit+iteration for more in-depth information. :)
On Tue, Jun 14, 2011 at 15:29, Kostas Karasavvas <[email protected]> wrote: > Very informative! Thank you Alan. > > K. > > > On 10 June 2011 18:00, Alan R Williams <[email protected]> wrote: >> On 10/06/2011 16:04, Kostas Karasavvas wrote: >>> Hi all, >> >> Hello >> >>> I have a question regarding the implementation of implicit iteration. >>> >>> Say we have: A -> B >>> A produces a list (say, with 5 elements) >>> B consumes a single element >>> >>> Will it iterate 5 times in sequence, i.e. call B, get results, call B, >>> get results, ... >>> Will it use threads, i.e. call B in thread1, call B in thread2, ... >>> Something else? Is it maybe configurable? >> >> The 5 calls of B do not have to happen in sequence. For example, if A is >> outputting its list as individual elements (rather than waiting for the >> whole list to be available and then outputting it), then A may produce >> element 3 before element 1. Because the call of B will happen for >> element 3 as soon as it is available, it will happen before the call >> corresponding to element 1. >> >> However, if you think of a list made up of the outputs of the 5 calls of >> B, then that list will still be in the right order i.e. the result of >> calling B for element 3 will be at position 3, that of element 1 at >> position 1. So, although the calls may have been made out-of-sequence, >> the overall result is in the correct sequence. >> >> Each service invocation happens in a separate thread, so yes Taverna >> uses threads for the calls of B. >> >> Whether several calls of B can be made at the same time, depends on the >> type of service that B is, and also on what has been specified for the >> number of parallel jobs for that service. >> >> There is only one beanshell interpreter for each beanshell service in >> the workflow, so although you can tell Taverna to run several parallel >> calls to that beanshell service, the calls will happen in sequence. >> >> For a WSDL service, Taverna can run calls in parallel. That can be >> dangerous though as it can have nasty effects on the machine where the >> remote service runs. >> >> To set the number of parallel jobs that Taverna will try to use for a >> service, you can r-click on the service, select "Configure running" and >> then "Parallel jobs". >> >>> Thanks, >>> Kostas >> >> Alan >> >> ------------------------------------------------------------------------------ >> EditLive Enterprise is the world's most technically advanced content >> authoring tool. Experience the power of Track Changes, Inline Image >> Editing and ensure content is compliant with Accessibility Checking. >> http://p.sf.net/sfu/ephox-dev2dev >> _______________________________________________ >> 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/ >> > > ------------------------------------------------------------------------------ > EditLive Enterprise is the world's most technically advanced content > authoring tool. Experience the power of Track Changes, Inline Image > Editing and ensure content is compliant with Accessibility Checking. > http://p.sf.net/sfu/ephox-dev2dev > _______________________________________________ > 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/ > -- Stian Soiland-Reyes, myGrid team School of Computer Science The University of Manchester ------------------------------------------------------------------------------ EditLive Enterprise is the world's most technically advanced content authoring tool. Experience the power of Track Changes, Inline Image Editing and ensure content is compliant with Accessibility Checking. http://p.sf.net/sfu/ephox-dev2dev _______________________________________________ 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/
