The target "depends" attribute already gives all the information you need to be able to determine which targets can be executed in parallel?
As I mentioned earlier the only road-block at the moment to a totally transparent mechanism for supporting parallel execution is the dubious implicit dependencies that the documentation for the "depends" attribute makes reference to. (and the great many build scripts in the wild that rely upon it :( ) ----- Original Message ----- From: Chuck Holzwarth To: Ant Users List Sent: Wednesday, December 19, 2007 2:33 PM Subject: Re: AW: extended parallelism The problem with giving a command line option is that ant is effectively a set of rules. The rules form a tree and the dependencies give a list of targets that are to be executed before the current target. There would have to be some intelligence in the build file that would show ant which tartets could be completed in parallel. For example, if you are using ant to compile C programs, the obj files that the executable requires must be completed before the linkage stage. There are areas where parallel processes can be leveraged, but ant will not be able to determine those places. In my experience, even the programmers who have written the code have difficulty identifying those places. In my case, there are times where parallem processing could be helpful. I retrieve the latest copy of all files from the repository for builds, I retrieve the CM log information, I create the release boiler plate file using information in a property file that is loaded at startup. These could all be executed in parallel. One part of the build that could not be executed in parallel is creation of the zip file that includes only the HTML files that changed since the previous release. These files are copied from the complete release zip files and can't be attempted until the zip files with the complete set of files is available. [EMAIL PROTECTED] wrote: > It may be better to stay away from a grammar that gives the > rules and use something like: > > > > ... > > You could provide another executor ;) In my approach I dont want the user to change the buildfile. Just set the property on command line. ant -Dant.executor.class=ParallelExecutor ... > How do you propose to handle potential fatal/non fatal > errors? The implementation collects thrown BuildExceptions from the target. A target will be started, if no dependend target has failed. Why not try to build the jar only because the test fails? If there is a dependency you should describe that dependency using the depends-attribute. >If target a exits due to an error, should there be an > option to kill a or allow it to complete (similar to > failonerror="yes/no")? If both a and (b,c) must succeed for > d, should a be killed if b or c fails? If you want to have that, use If there is no dependency - why stop the build? > It was not difficult, but error handling was always the issue. My biggest problem is spreading all the logs. In a single thread you have output like target-1 target-1 target-2 target-2 When parallelizing that you could earn target-2 target-1 target-2 target-1 I thought about using a logger per thread Logger log = Logger.getLogger( targetName + "." + threadNumber ); Jan --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Thank you, Chuck Holzwarth (804) 403-3478 (home) (540) 335-3171 (cell) --------------------------------- Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. ________________________________________________________________________ E-mail is an informal method of communication and may be subject to data corruption, interception and unauthorised amendment for which I-play, a trading name of Digital Bridges Ltd will accept no liability. Therefore, it will normally be inappropriate to rely on information contained on e-mail without obtaining written confirmation. This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden. (C) 2005. I-play is a trademark and trading name of Digital Bridges Limited. All Rights Reserved. ________________________________________________________________________ This message has been checked for all known viruses by the MessageLabs Virus Scanning Service. For further information visit http://www.messagelabs.com/stats.asp