[React Native] recomputeNewValue/reallyRecompute performance issue with persistent cache

[IvanIhnatsiuk]

Issue Description

The main problem is that persistent query restoration takes a lot of time. For example, in this project, we have 200 poke entities, and recomputeValue takes ~80–90ms. On real projects, there might be huge objects/arrays with deeply nested data.

I think the root issue is that makeDepKey needs to iterate over every field in objects nested inside arrays, which means it fully blocks the render thread (main JS thread). This traversal becomes very expensive, and combined with the GC pressure, it slows things down significantly. In particular, the Hermes engine shows long pauses in the young generation garbage collector because of the volume of short-lived objects being created during this deep iteration.

Profiler stacktrace:

Trace-20250928T234034.json

Link to Reproduction

https://github.com/IvanIhnatsiuk/apollo-cache-performance

Reproduction Steps

1. Run the project.
2. Uncomment the query to fetch data from the server.
3. Comment out the line again.
4. Re-run the project.
5. Start the performance profiler.
6. Click "Show Cached Data" to render SubComponentWithCachedData.
7. Observe the performance degradation.

@apollo/client version

4.0.6

[IvanIhnatsiuk]

Note:
This issue also occurs with Apollo Client v3.

[jerelmiller]

Hey @IvanIhnatsiuk 👋

Appreciate the issue! This one is fairly big to unravel and we've got some other priorities we are focusing on right now. I can't guarantee we will be able to look at this anytime soon, but the reproduction is helpful. If you've got some suggestions, we'd appreciate it!