Sync hangs on large folders

[marco-polo-github]

Actual behaviour

Syncing of a large folder with a lot of sub folders does not finish. The files in the subfolder structure at the phone are not updated, I need to referesh that manually on my nextcloud app then, it starts to download the files, but not before. Also the app hangs after starting the sync, and android asks me to wait / close the app.

Expected behaviour

The content should be updated on the device if I press sync in the android app. In my opinion, there should be a current status from the app and the notification should be updated for an ongoing process. Folder and file structure should be checked on every sync. IMHO the sync only in direction to the android app should not stop because of upload problems (e.g. upload to the server does not work because of insufficient rights).

Steps to reproduce

1. add files to the nextcloud server with e.g. PC
2. sync the folder on the android app

Environment data

Android version: 9
Kernel: 4.9.59-15540155

Device model:
Samsung Galaxy S9+
SM-G965F

but I have the same issue on a:
Sony Z1 compact with AOIP Android 8.1
Sony Z3 With Lineage OS Android 9
Samsung Note3 LineageOS 14.1

Stock or customized system:
both

Nextcloud app version:
3.5.1
Nextcloud server version:
15.0.5
but the error was also in version 14.x.x

Logs

Web server error log

Insert your webserver log here

Nextcloud log (data/nextcloud.log)

Insert your Nextcloud log here

NOTE: Be super sure to remove sensitive data like passwords, note that everybody can look here! You can use the Issue Template application to prefill some of the required information: https://apps.nextcloud.com/apps/issuetemplate

[nextcloud-android-bot]

GitMate.io thinks possibly related issues are #285 ([TOP] Enhance sync folders), #668 (Folder sync), #2559 (Missbehaviour on syncing big folders), #3760 ([F] sync photo folder), and #791 (Improvement: arbitrary synced folders).

[stale]

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