Performance issues

[Moskacz]

Hey,

thanks for this framework, it's very good and improves architecture of my app. However I have small performance issues when resolving components, it could take even 200ms on new device (iPhone 7). The component that I want to resolve is quite 'heavy' because it takes 4 other components as init parameters and each of this parameters has other dependencies. Is there any way that I can improve this performance?

Cheers,
Michal

[ilyapuchka]

Hi @Moskacz . You can try improve performance by not using autowiring and containers collaboration, ensuring that you explicitly resolve components with containers where they are registered in.

[Moskacz]

@ilyapuchka thanks for replying, I don't use container collaboration, but I do use autowiring. What should I use instad? Let's say that I have definitions like this:
container.register { URL(string:"http://myserver.com" }
container.register { HttpClient(url: $0) }

then should I convert second definition to:
container.register { (url: URL) in HttpClient(url: url) }

is this correct?

[ilyapuchka]

With this you will need to provide url as a parameter when resoling HttpClient, which is not very convenient.

let url = try container.resolve() as URL
let client = try container.resolve(arguments: url) as HttpClient

instead you can do it like this:

container.register { URL(string:"http://myserver.com" }
container.register { [unowned container] in try HttpClient(url: container.resolve()) }
let client = try container.resolve() as HttpClient

This will save some extra loops to find all the dependencies.

[Moskacz]

You're right. Thanks, I'll remove autowiring, and see how it performs.

[Moskacz]

Performance has improved by ~25%. Is there anything else I can do to improve it further?

[ilyapuchka]

The other thing that comes in mind that might affect performance is circular references. It might happen that some objects are created twice and then it will result in a performance hit if it's a heavy operation. You can read more here https://github.com/AliSoftware/Dip/wiki/circular-dependencies
So inspect your code on that issue.

Otherwise I would suggest to profile your app and see where is the bottle neck, it might not be in DI at all.