App Freezing with Large Datasets – Possible Platform Change?

We’ve been using a Retool app that loads ~4,000–5,000 records from an API and runs a few lightweight JavaScript queries to compute some metrics and feed charts. This setup used to work fine, even with large data sets.

But recently (as of 05/17/25), we’ve noticed serious performance issues: the browser memory usage shoots up to over 20 GB, and the app becomes unusable.

What’s odd is that even older, previously stable versions of the app are now affected, so it feels like something might have changed on the Retool side (possibly how data or JS is handled?).

Here’s what we’ve already checked:

  • Removed unnecessary query triggers and event handlers
  • Refactored JS code to avoid heavy transformations or deep copies

We’d love any insight on whether something changed behind the scenes recently that could be impacting this, or if others are seeing similar behavior.

Hi @ivan_wi,

Apologies for the issue, that is very odd that it had been working previously and since 5/17 now has issues.

This sounds like it could be the result of an update to Retool (assuming you are on cloud), if you are able to export your app with query data included, I can test it out and share this with our performance team to see if they can find any clues that we can use to resolve this.

To export an app to JSON with query data included, you can click on the export button from the debug panel once the queries have run and the components are populated.

Hi Jack,

Thanks for following up here,

Just wanted to follow up and confirm that the issue appears to be resolved as of version v3.218.0-96edc9e. We've been monitoring the app over the past few days, and memory performance is now stable, even with large datasets and tables rendered.

Really appreciate the support on this - the fix made a big difference for our engineering team.

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That is great to hear!

Happy that the issue appears to be resolved and sorry you had to deal with that in the first place.

Let me know if anything changes :sweat_smile: