Hi, We were profiling the loading of code that uses many Traits. We saw something like this (this is a tally for `TraitedMetaclass>>#addAndClassifySelector:withMethod:inProtocol:`): [image: Screenshot 2022-05-11 at 17.17.37.png] From what we saw in `TraitedMetaclass>>#addAndClassifySelector:withMethod:inProtocol:` a method is first added to `localMethodDict` and then it calls the super method that adds the selector to the `methodDict` of the actual class in `Behaviour>>addSelectorSilently:withMethod: `. Because of this we basically get an overhead as a method is added to two method dictionaries and adding a method to a MethodDictionary is slower, as it does operations like `flushCache` and `cachePragmas`. Should the `localMethodDict` also be an instance of MethodDictionary or could it be a simple dictionary? Cheers, Andrei

Marcus

> On 12 May 2022, at 11:27, Andrei Chis <chisvasileandrei@gmail.com> wrote: > > Hi, > > We were profiling the loading of code that uses many Traits. We saw something like this (this is a tally for `TraitedMetaclass>>#addAndClassifySelector:withMethod:inProtocol:`): > <Screenshot 2022-05-11 at 17.17.37.png> > > From what we saw in `TraitedMetaclass>>#addAndClassifySelector:withMethod:inProtocol:` a method is first added to `localMethodDict` and then it calls the super method that adds the selector to the `methodDict` of the actual class in `Behaviour>>addSelectorSilently:withMethod: `. Because of this we basically get an overhead as a method is added to two method dictionaries and adding a method to a MethodDictionary is slower, as it does operations like `flushCache` and `cachePragmas`. > > Should the `localMethodDict` also be an instance of MethodDictionary or could it be a simple dictionary? > I think it can be normal Dictionary: MethodDictionary we just meed where there VM executes code (for flushCache) and for lookup. The only downside is that it then uses a little bit more memory (MethodDictionary does not use associations), but that should be no problem. Marcus

     Marcus

On Thu, May 12, 2022 at 3:19 PM Marcus Denker <marcus.denker@inria.fr> wrote: > > > > On 12 May 2022, at 11:27, Andrei Chis <chisvasileandrei@gmail.com> > wrote: > > > > Hi, > > > > We were profiling the loading of code that uses many Traits. We saw > something like this (this is a tally for > `TraitedMetaclass>>#addAndClassifySelector:withMethod:inProtocol:`): > > <Screenshot 2022-05-11 at 17.17.37.png> > > > > From what we saw in > `TraitedMetaclass>>#addAndClassifySelector:withMethod:inProtocol:` a method > is first added to `localMethodDict` and then it calls the super method that > adds the selector to the `methodDict` of the actual class in > `Behaviour>>addSelectorSilently:withMethod: `. Because of this we basically > get an overhead as a method is added to two method dictionaries and adding > a method to a MethodDictionary is slower, as it does operations like > `flushCache` and `cachePragmas`. > > > > Should the `localMethodDict` also be an instance of MethodDictionary or > could it be a simple dictionary? > > > > I think it can be normal Dictionary: MethodDictionary we just meed where > there VM executes code (for flushCache) and for lookup. > Ok. I can experiment with replacing it with a Dictionary and see how it goes. > > The only downside is that it then uses a little bit more memory > (MethodDictionary does not use associations), but that should be no problem. > Indeed that's an interesting aspect. Maybe more important for the Pharo image is memory rather than loading speed. Cheers, Andrei > > Marcus >