14 Oct 2017

LifetimeTracker – Find retain cycles / memory leaks sooner.


LifetimeTracker can surface retain cycle / memory issues right as you develop your application, and it will surface them to you immediately, so you can find them with more ease.

Instruments and Memory Graph Debugger are great, but too many times developers forget to check for issues as they close the feature implementation.

If you use those tools sporadicaly many of the issues they surface will require you to investigate the cause, and cost you a lot of time in the process.

Other tools like FBRetainCycleDetector rely on objc runtime magic to find the problems, but that means they can’t really be used for pure Swift classes. This small tool simply focuses on tracking lifetime of objects which means that it can be used in both Objective-C and Swift codebases and it doesn’t rely on any complex or automatic magic behaviour.



Add pod 'LifetimeTracker' to your Podfile.


Add github "krzysztofzablocki/LifetimeTracker" to your Cartfile.


To Integrate visual notifications simply add following line at the start of AppDelegate(didFinishLaunchingWithOptions:):

  LifetimeTracker.setup(onUpdate: LifetimeTrackerDashboardIntegration().refreshUI)

Tracking key actors

Usually you want to use LifetimeTracker to track only key actors in your app, like ViewModels / Controllers etc.

You conform to LifetimeTrackable and call trackLifetime() at the end of your init functions:

class SectionFrontViewController: UIViewController, LifetimeTrackable {
    static var lifetimeConfiguration: LifetimeConfiguration = (identifier: "VC", maxCount: 1)

    override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
        super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
        /// ...

When you have more than maxCount items alive, the tracker will let you know.


LifetimeTracker is available under the MIT license. See LICENSE for more information.


I’ve used SwiftPlate to generate xcodeproj compatible with CocoaPods and Carthage.



Source: https://github.com/krzysztofzablocki/LifetimeTracker

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