[LVS] Update to 1.13.1? [We did it!]

[Zedwick]

It has been 2 and a half months since the great time warp, and though 1.13.1 has been released we unfortunately did not see all of the world upgrade problems resolved. However, thanks to the wonderful larger Minecraft community, I believe it may be safe (enough) to upgrade using community-created patches.

There are some other relatively minor issues still, which I will do my best to describe below. Please bear in mind though that these are only the known issues (which I am personally aware of), there may be other rarer issues not covered here.

Nether fortress not spawning wither skeletons or blazes
https://bugs.mojang.com/browse/MC-133992

Nether fortresses generated in 1.12.2 or earlier may not be recognised as a fortress and continue to spawn blazes. The issue has been confirmed by multiple people, but the root cause of the issue does not appear to have been directly identified yet.

A similar report, https://bugs.mojang.com/browse/MC-125377, desribes other structures like Ocean Monuments not spawning structure-specific mobs within the structure after upgrading from 1.12.2 to 1.13 snapshots. This bug has been marked as resolved, but appears related.

Though this could cause some existing farms to be completely broken in 1.13+, it is potentially something which could be patched post-upgrade by inserting the data on the structure into the world files at a later date. However, I cannot make any guarantees.

Containers next to chunk borders can lose items when upgrading
https://bugs.mojang.com/browse/MC-134115

Double chests across chunk borders may have half their contents wiped. The root of this issue has been identified by the community and multiple different methods to fix this have been created. This issue is no longer a concern for us when updating to 1.13.1.

World upgrade is not proceeding correctly
https://bugs.mojang.com/browse/MC-136510

At a cursory glance appears to primarily affect non-vanilla-survival objects, the example given looks to be a spawner in a minecart which spawns Polar Bears (something not found in vanilla survival worlds without use of commands to create it). I do not expect this to affect our survival worlds, beyond edge cases where a Zedwick may have at some time created an unusual item for an event using commands.

Upgrading only unlocks oak button, pressure plate and trapdoor recipes and advancements
https://bugs.mojang.com/browse/MC-132442

1.13 has flattened many blocks from a single material (wooden_door) to many (oak_door, acacia_door, etc.). As the existing advancements and recipes covered all wood types with a single material, it is not possible to seperate them out and decide which the player would have truly unlocked during the upgrade process. So only the oak variant of the advancements and recipes are unlocked during the upgrade. The other variants can still be unlocked by the player after the upgrade.

TileTicks upgrader could cause update for unintended block
https://bugs.mojang.com/browse/MC-123692

Could cause blocks which did not have an update scheduled to update after the upgrade process. May under rare circumstances cause some complex redstone machines to temporarily break or mis-fire until manually reset.

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I would like to know, given these issues and that the chest wiping bug fix has not come from Mojang, do you think it is time to update? Once we update, we will not downgrade again unless there are serious problems. I may not be able to patch small instances of data loss should they crop up, though I do not expect any to arise beyond the above listed structure mob spawning issue.

[Dax23333]

Structures being wiped would be a big one if it hit. In the time warp neither the Bone Yard, Paradise Prismarine Farm or the Fish Basement were affected which if I understand the report correctly they could have been. If this has any bearing on what the behavior this time will be I do not know but I am hopeful. This may well be blind optimism.

Good to know the chest issue is gone! Although honestly I do not think this would be that major on its own anyway. And apart from that we might expect some running redstone machines to muck up, if thats it I think it'll probably be ok.

As long as I get to keep all of my base (rather than lose about 2/3 of it) when lvs updates I think it is a good idea to do so.

[Zedwick]

If anyone with existing mob farms, particularly farms which rely on nether fortresses, would like to provide the coordinates to them here I may give upgrading those areas a try to see if I encounter any problems upgrading them to 1.13.1.

[Dax23333]

Ok, I've checked the coordinates of the major public ones I know of.

222 43 1969, Bone Yard (Nether fortress farm)
11574 11 8929, Fish Basement (Prismarine farm)
-3342 6 355, Paradise Prismarine Farm (Guess)

Might be a couple more, the fortress farm off Extreme Hills springs to mind but that was made obselete by the Bone Yard.

[tim]

I think its time to upgrade but to be sure could we announce the day it happens at the next council meeting and warn in the chat when u login. Then call for a 48 hour check period where we revert at the first sign of trouble so people won't start crazy builds only to be reverted. Anyway good work zed keep it up!

[Zedwick]

I have tested the upgrade on the three farms Dax provided, and found that the Pirsmarine farms are fine, however the Bone Yard appears to be only spawning Zombie Pigmen.

[SooprJ]

Are blaze spawners possibly affected? Or is it only nether fortress mobs naturally spawning thats affected?

[Zedwick]

Are blaze spawners possibly affected? Or is it only nether fortress mobs naturally spawning thats affected?

The bug listed above should only affect mobs spawning naturally in a fortress. I am not aware of any issue which would affect mob spawners. Though they might generate in a structure, their ability to spawn mobs is not tied to the structure.

[Zedwick]

After further testing, and discussion with Dax, I have the bone yard working in my test upgrade. So my amended results show that all the listed farms work fine when upgraded to 1.13.1.