| Re: [epsilon-dev] IPropertyGetters/Setters in Models |
This turned out to be a classic case of premature optimisation. I assumed that because some models were caching this, it would be the right thing to do, and when I changed it all tests were passing. However I had missed the PropertySetter in EmfModel, and when I changed this two tests failed and I realised there is state involved. I’ll carefully look at this and revert the changes, and see if there is a better way. From: Sina Madani Hi Dimitris, Thank you for the clarification. It appears this was mainly an issue in JavaModel, PlainXmlModel, XmlModel and AbstractEmfModel. The others were all using a propertyGetter/propertySetter field, so I have moved this to the Model class and updated extensions accordingly so that the appropriate type is assigned in the constructor. Thanks, Sina From: Dimitris Kolovos Hi Sina, This looks like an oversight. I can't see any reason why we shouldn't be reusing stateless property getters/setters. Cheers, Dimitris On Mon, 27 Apr 2020 at 00:20, Sina Madani <sinadoom@xxxxxxxxxxxxxx> wrote: > > Hi everyone, > > > > I noticed that the getPropertyGetter and getPropertySetter implementations in a lot of models (including PlainXml and Emf) return a new instance every time. Since property accesses are frequent (could be tens of millions of times per program), this results in a lot of unnecessary objects being created and GC’d. I was wondering if this is a bug in the implementation (perhaps a programming mistake), or part of the design? Since judging by the implementations of the getters/setters, there isn’t any state stored – these are effectively pure functions. If so I propose to cache all property getters and setters, which should in theory drastically reduce memory allocations. Intuitively it seems like a costly oversight in the design (in terms of performance) if this is the case, so please let me know if I’m missing something. > > > > Thanks, > > Sina > > _______________________________________________ > epsilon-dev mailing list > epsilon-dev@xxxxxxxxxxx > To unsubscribe from this list, visit https://www.eclipse.org/mailman/listinfo/epsilon-dev -- Dimitris Kolovos Professor of Software Engineering Department of Computer Science University of York http://www.cs.york.ac.uk/~dkolovos EMAIL DISCLAIMER http://www.york.ac.uk/docs/disclaimer/email.htm _______________________________________________ epsilon-dev mailing list epsilon-dev@xxxxxxxxxxx To unsubscribe from this list, visit https://www.eclipse.org/mailman/listinfo/epsilon-dev |