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setState very slow

See original GitHub issue
    public addShowInfo(showInfo: ShowInfo) {
        console.log("start set showinfo state")
        this.setState({ showInfo: showInfo }, ShowInfoStoreActions.AddShowInfo);
        console.log("finish set showinfo state")

I have this simple setState which takes about 3-4 seconds to run. Any idea why?

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Comments:7 (4 by maintainers)

github_iconTop GitHub Comments

DanWahlincommented, Apr 2, 2020

As a heads-up, due to some edge cases that came up I ended up having to do deep cloning when setting and getting state even in production. So, if you’re still using it to store large amounts of data you may see an impact with v2.2.8. However, setState() and getState() now have a deepClone boolean property that can be passed ( So, when adding all of the records you mentioned above you could do something like the following potentially:

this.setState(yourState, 'Your Action', true, false); this.getState(false)

The last false value would tell it to NOT do a deep clone on the state being added. That’s good for performance, but any changes to the data outside of the store could affect the store data since it’d be stored by reference without any cloning in that case.

DanWahlincommented, Dec 28, 2019

Awesome! Good to hear. Heard about that trick (deep cloning in dev to prevent mutations and shallow cloning in prod) from one of the NgRx guys.

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