Backups are inconsistent and unreliable

[amihsekai]

Your GTNH Discord Username

blindiota

Your Pack Version

2.8.2 and 2.8.3

Your Server

SP

Java Version

Java 25

Type of Server

Single Player

Your Expectation

Backups are supposed to be a safety net. If something goes wrong, I expect to be able to restore my world to a recent and consistent state with minimal progress loss.
I've set them to run every 3 minutes, so they happen very frequently.
Restoring a backup should put my inventory and world state exactly as they were at that time.

The Reality

Despite being set to run every 3 minutes, sometimes they just stop working, and even when I run /backup start no 'Backup done' notification appears sometimes.
My horse disappeared and I couldn't find it. Whatever happened, I thought I could rely on a backup, just to find out my last one was about 5 hours before, with significant progress behind (exploration and base expansion). I always keep automatic backups enabled.
I proceeded playing without reverting, searching for another horse far away. On the way home, an aura node caught me and my horse died (I also couldn't find the saddle it should've dropped). My patience was thin, so I reverted to the previous backup, which was from a couple of minutes earlier (the moment before I found the horse). Then, I found out the saddle was gone from my inventory.

It's dangerous if these issues keeps happening at any point of the game.

OBS: I actually have set the backups to run every 3 minutes because the unreliability was becoming really stubborn.

Your Proposal

Review the backup system.

Final Checklist

• I have searched this issue tracker and there is nothing similar already. Posting on a closed issue saying the bug still exists will prompt us to investigate and reopen it once we confirm your report.
• I can reproduce this problem consistently by follow the exact steps I described above, or this does not need reproducing, e.g. recipe loophole.
• I have asked other people and they confirm they also have this problem by follow the exact steps I described above, or this does not need reproducing, e.g. recipe loophole.

[spacebuilder2020]

I have also noticed that sometimes an item will be out of sync. My guess is that the backups do not disable saving and during a long backup cycle it is possible for something to get missed. I have had my own similar issue with my backups after playing with distant horizons where it took a lot longer because it had to backup a database file. (I solved it by doing a quick and dirty modification to the backup logic to exclude that file, but since it is timing related, I could still run the risk of loosing something small.)

I noticed logic that explicitly saves all player data, so it is possible it could save an intermediate state, but the state of the other files don't update before the backup of the world is ran.

That said, from a personal note, I don't consider backups a general safety net but a way to restore if something catastrophic happens. Personally, if you need that extra reliability, I would suggest setting up a local server on your machine and doing the classic backup method. (save-all, save-off, ... xcopy all the files to your backup folder ... save-on). You could also look into a dedicated backup mod such as AromaBackup.

[spacebuilder2020]

A way to mitigate this issue would be to move the save all player logic up to before all of the worlds are saved. Since the world save also saves this data, by moving it up, it would ensure that the player inventory is in sync with the world the users are in and while it might be unnecessary, having it there may also help in some cases.