[Bug]: [A-force] File Upload Timeout Issue for Files Over 15MB on Appsmith Version v1.61

[NilanshBansal]

Is there an existing issue for this?

• I have searched the existing issues

Description

Summary: The user is on v1.61 and gets an error when uploading files larger than approximately 15MB using a POST request with multipart/form-data in Appsmith: Upload error: { "message": "Response not valid" }. The request is routed through an AWS Load Balancer to their Java backend, which successfully handles large files when requests are made directly through tools like Insomnia or Postman.
In Appsmith, smaller files are processed without issues, but for larger files, uploads fail exactly after 15 seconds, even though they have set a timeout of 30 seconds for the API. The maximum file size for the file picker is already set to 100MB.
They use AWS appsmith-ee AMI that runs on a t3a.xlarge instance 4 vCPUs, 16.0 GiB. They also configured the upload file size limit using this doc: https://docs.appsmith.com/getting-started/setup/instance-configuration/file-size-limit but are facing the same issue.
Link: https://internal.appsmith.com/app/oracle/ticket-details-662d74ffc3e4d34941e56ede?zid=cnv_1fyic5n0
Ref: https://theappsmith.slack.com/archives/C0341RERY4R/p1741340059104339

Steps To Reproduce

Ref: https://theappsmith.slack.com/archives/C0341RERY4R/p1741340059104339

Public Sample App

No response

Environment

Production

Severity

Medium (Frustrating UX)

Issue video log

No response

Version

Self Hosted v1.61

[NilanshBansal]

Call setup with the user on 9th April.
https://theappsmith.slack.com/archives/C0341RERY4R/p1742806381332389?thread_ts=1741340059.104339&cid=C0341RERY4R

@appsmithorg/performance-pod can someone buddy me on this call with the user?