I haven't found out how to start more than one feature at once. I would think that having some way to start a feature asynchronously would be useful, but I think adding a system beyond startlevel to determine bundle start order is not likely to work well.
When would it be a problem to start a bunch of features aysnchronously at once? thanks david jencks On Mar 3, 2011, at 8:18 PM, Andreas Pieber wrote: > OK, another feature proposal for 3.0: > > I've the following "problem" with the OpenEngSB project right now. We > have different features where some are optional, but if they are > defined they could also start in parallel. E.g. assume you have > feature A and feature B. Feature A requires some time to come up since > it requires some time to get all blueprint services wired, BUT feature > B does not need to wait till feature A is finished but could rather > startup with feature A (as if they're defined in the same feature). > > I can think of two solutions for the problem > > 1) Define parallel startup in features.cfg. In Archlinux you have a > Daemons array defined saying which services to start during the boot > which looks something like: > > DAEMONS=(syslog-ng netfs crond dbus !network wicd @acpid @cups @ntpdate @mpd) > > This means now: first start syslo.. then netfs, then crond (one after > the other, similar to our feature file), but you don't have to wait > for acpid, cups, ntpdate to wait, start them up and go ahead (thats > what the @means). > > I can think of the same for Karaf: > > A,@B > > which could mean: start feature A and feature B like they where the same > feature > > 2) A different solution could be to add a new tag to the features.xml > listing the features with which a feature could be started in parallel > ---> > > Feature B could contain: > > <couldBeStartedTogetherWith><feature version...>A</feature><feature > version...>OTHER_FEATURE</feature></couldBeStartedTogetherWith> > > ------------ > I think it may be good to support borth options since the feature > developer should now best with which features his feature could start > in parallel, BUT the feature developer can not imagine each possible > feature which could be started in parallel with his feature. > > So, WDYT? :) > > Kind regards, > Andreas
