perf: improve native apps startup

[hurali97]

Details

The changes in the PR are part of improving the app startup which was profiled for the native Apps. The main change is explained below, the other changes are self explanatory.

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Prior to the following change, we had 2.4 seconds being consumed in the loop. We can improve this by doing a `multiGet` and then doing a loop over returned keys. This reduces the execution time to 250 ms, saving us 2 seconds.

Before:

After:

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Related Issues

Expensify/App#43746

Automated Tests

Manual Tests

Author Checklist

• I linked the correct issue in the ### Related Issues section above
• I wrote clear testing steps that cover the changes made in this PR
  • I added steps for local testing in the Tests section
  • I tested this PR with a High Traffic account against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
• I included screenshots or videos for tests on all platforms
• I ran the tests on all platforms & verified they passed on:
  • Android / native
  • Android / Chrome
  • iOS / native
  • iOS / Safari
  • MacOS / Chrome / Safari
  • MacOS / Desktop
• I verified there are no console errors (if there's a console error not related to the PR, report it or open an issue for it to be fixed)
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  • I verified that any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick)
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• I tested other components that can be impacted by my changes (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar are working as expected)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
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  • The only data being stored in the state is data necessary for rendering and nothing else
  • If we are not using the full Onyx data that we loaded, I've added the proper selector in order to ensure the component only re-renders when the data it is using changes
  • For Class Components, any internal methods passed to components event handlers are bound to this properly so there are no scoping issues (i.e. for onClick={this.submit} the method this.submit should be bound to this in the constructor)
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• I have checked off every checkbox in the PR author checklist, including those that don't apply to this PR.

Screenshots/Videos

Android: Native

android.mov

Android: mWeb Chrome

android-web.mov

iOS: Native

ios.mov

iOS: mWeb Safari

ios-web.mov

MacOS: Chrome / Safari

web.mov

MacOS: Desktop

desktop.mov

[chrispader]

As @hannojg already suggested, we definitely want to preserve the ability to get the value from cache rather than from storage in Onyx.connect.

[neil-marcellini]

Looks great overall. I think we can re-use some existing code.

I'm also curious if the for in loops are really helping performance / memory use or if that was just a preference. Disabling eslint is probably fine because I don't think we'll have prototype properties getting in the way, but let's only disable the rule if there's a good reason.

[chrispader]

LGTM except for the changes that were already mentioned

[hurali97]

Looks great overall. I think we can re-use some existing code.

I'm also curious if the for in loops are really helping performance / memory use or if that was just a preference. Disabling eslint is probably fine because I don't think we'll have prototype properties getting in the way, but let's only disable the rule if there's a good reason.

Comparing the before and after profiles, we get 400ms of reduction if we use for...in mainly because we are not doing Object.keys first for target and second for source. These numbers are really noticeable on a large data like ~15k reports.

[hurali97]

@chrispader @hannojg suggested changes are addressed, would be great to if you guys can re-review 👍

[mountiny]

@hurali97 mainly comment changes requested.

@chrispader @hannojg can you give this another look please?

[chrispader]

LGTM!

[mountiny]

Thanks! @neil-marcellini all yours

[hoangzinh]

LGTM. Tested well

Screenshots/Videos

Web

Screen.Recording.2024-06-26.at.01.46.51.mp4

IOS

Screen.Recording.2024-06-26.at.01.56.28.mp4

[neil-marcellini]

Looks really good, thank you.

[neil-marcellini]

@hannojg do you want to review once more before we merge? @mountiny feel free to go ahead if you want.

[mountiny]

Lets get this one going thank you very much!

[github-actions]

🚀Published to npm in v2.0.54