I have a 3 year old server that I operate that we launched with the 1.17 update. It is also having this issue of trial chambers not giving loot after the mobs have been defeated.
Edit2: Investigated further... it's more specifically ACTIVE pathfinding... the more villagers that have something they want to do... find a bed... escape danger... pick crops... whatever... the game lags tremendously... where as if they are just idle pathfinding... wandering around, the game performance seems to be uneffected, atleast to a noticable degree
Edit: I figured it out! It has to do with farmers either being able to harvest crops, or being able to plant crops (or both). I tested this by trying different single villager profession setups.... and out of my tests. I had no issues at first with any of them, but with the farmers, I decided to temporarily increase the tic rate just to grow the crops, then turn it back down... as soon as crops were harvestable, the world turned to a slideshow... killing off the farmers would fix the issue... adding them back in would bring the issue back.
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I have tested this in my world... and it seems to me like the issue is not directly tied to villagers... but instead tied to entitites...
Example: I go to my 40 villager trading hall, or a smaller village... and I do not get entity lag... things like punching grass or dropping items all happen smoothly and as expected.
I go to an area with a lot of crops planted... and the level of lag is to a point of being unplayable... chests take 5-10 seconds to open... grass can take 5 seconds to break once punched, etc.
Can also confirm. From information I can gather, it is effecting all BDS servers, and possibly all single player worlds that have been previously run on a BDS. No clue about realms. Also reporting I am hearing says it is from 4x4 and 9x9 crafting recipe's that use all 1 material to craft. Can also confirm manual crafting does not work. Screenshot attached.
[media]Added context. Trident killers using the looting effect are a required part of Minecraft Bedrock edition gameplay to balance the game further towards Java. Java edition has a much larger mob spawn rate, and mob cap, which allows all of it's hostile and passive mob farms to be incredibly faster than Bedrock Edition's farms. It also helps make up for the lack of Bedrock Edition not having sweeping edge, which allows for Java players to quickly kill large numbers of mobs with a single attack, getting the looting effect applied to all mobs killed. Bedrock does not have an equivalent to this.
Trident killers are used to bridge this gap.
I believe that spiders are also effected by this bug, as you can block off a 2x2 spawning location, and if you have a valid 1x1 spot, the spiders will still spawn. here is a screen shot of a design I was attempting, 3x3 platforms with the middle block covered by a button, and also I put signs in the gaps, the spiders seem to spawn on the outer edges of the blocks, partially inside the signs.
Sounds like you are doing it with blocks on the opposite side of the gap rather than open space. I just tested this last night, if you simply make a platform, place a creeper, place buttons around the outside, and place a cat, the creeper will not jump off the edge. The piglins and soul fire will eventually, but they don't run off right away like they used to.
I will add further information to this bug, it has to do something with what the magma cubes are checking for while spawning, they are ignoring spawning rules based on surrounding blocks (therefore they can spawn in a 1x1 spot with other blocks around them) but you can block their spawns to their correct 3x2.5x3 spawning requirement with armor stands, or lava. You should be able to block their spawns with almost any other block in those spaces, such as buttons, signs, trap doors, or other solid blocks.
The issue seems to be the way in which villagers are designed to link with beds and workstations, from what I can tell, it has to do with the order in which they are added to the village, meaning if you move villagers into an existing area with workstations and beds, or, add work stations and beds to an area with existing villagers, you never know what villagers are going to link where, and if the villagers are too far away, not on the right Y level, or something is blocking their path, they will fail to link, and not try linking to anything else.
The entire linking or syncing process needs to be redone. The villagers should do a check for the closest bed and workstation to them, first check if it is available, then check to see if he can pathfind to it, and if both of those answers are yes, he will sync up, then the pathfinding check should be redone periodically to maintain sync. This would allow you to add villagers or profession blocks whenever you would like, to block villagers up in their own stalls or homes with a bed and profession block and force them to sync to it, or close a path to get to a bed or block to break sync when you want to.
This broken mechanic worsens the existing bug that can cause a whole village to reset itself, unlinking every villager from their bed, and if you have them closed off in different areas, making it impossible to re-link them. This broken mechanic effectively ruins villager trading halls, iron farms, and villager based crop farms for any long term use.
The problem mainly comes in how the villagers prioritise what blocks to sync up with. It seems to be based on the order in which the villagers, and the blocks, are added to the village. Every so often the village jumbled this data up, causing them all to reset.
The whole villager sync portion just needs to be changed, making villagers check for beds and profession blocks based on how close they are to them, once synced he stays synced as long as he can still reach the bed and block... if he can't, he then scans again for the closest unclaimed bed and block he can get to, and will sync with those.
Also, profession blocks need to be able to be turned off, so they can be used as decoration without messing up villagers.
You also cannot use bonemeal to grow the kelp, micro kelp farms are out now too.
I did some testing on this bug. What it looks like happened is when Mojang fixed the issue with mobs spawning on blocks they weren't supposed to, they actually instead of only removing the ability for mobs to spawn on those blocks (glass, bottom half slabs, blocks with buttons, signs, etc on them) they actually made it so the mobs wont spawn anywhere at all on that Z axis.
Maybe for how you play it is, but I have builds that have use hundreds of pistons and well over 1000 hoppers, and 32 ingots an hour doesn't come close to cutting it.
Not sure if this has been said, but it seems that it's mob collisions that have all, or the biggest effect with the trident, the more mobs you flush through the killer, the more dislodged the trident become. I have seen dozens of attempted fixes to this, nothing works as good as the old killers, that will kill fast enough, all mob types, without losing trident and having mobs ghost through blocks.
If you are testing this on your end, let it run for 10-15 minutes while actively killing mobs. It'll break.
Sorry about the link, video is going live right now, had to create the bug reports prior to making the video so I could reference them all.
Also did not see this other magma cube one, thanks! The info in it seems to only speak to the 3x3 floor area that should be required, not the height. His testing used a 3 height ceiling and magma cubes should require a 2.5 height to spawn.
I've noticed it even when playing on a realm alone. It has killed insta-mine as you now have to re-mine a lot of blocks 3 times to get the game to actually remove it.
Want to replicate this bug yourself? Just take an efficiency 5 diamond shovel and go dig up some sand.
Yes
1) plant a field of potatos and allow for final growth stage
2) place a farmer villager in with the potatos, and a non farmer villager in with him
Observed results: the farmer will harvest a few potatos, will go to the other villager as if to throw the potatos to him, but will not throw them. Farmer villager will not continue to harvest crops
Expected result: the farmer villager should share the potatos by throwing them to the other villager. This works with carrots.
Additional info: if you give the villager potatos out of your inventory, he will trade them. This issue only pertains to potatos harvested by the farmer.
I have further observed this happening, the farmers will still go to the villager they would like to trade to as if they want to trade, but they are just unable to throw the potatos
I have provided a world download of the old pre 1.11 iron farm design, and 2 different iron farm designs I have used personally. I will be releasing a video based on this world tomorrow.
https://www.dropbox.com/s/aegle1v22wyw376/iron%20farm%20bug.mcworld?dl=0
The issue is you can't scale up on bedrock, you get 40, or you get 40. Docm has a pretty easy to make iron farm with 10k per hour rate, where as now ilmango has a huge complex farm with 150k per hour rate. I'm not even asking for those rates honestly. Just much better than 40.
I have had this issue with armorstands as well, started with the .30 update. Happens on the BDS server I play on, and occurs during load times, first noticed it when loading back from the nether, but could also be on world load as well. Have had reports from my community that it is also occuring on realms, and on single player worlds.
Regarding the comments about other entities clipping through blocks. I have experienced this with villagers, also happening only on world load / nether portal use. For non-armorstand, living entities, this is not causing clipping through the ground, but is causing mobs to clip through adjacent blocks, and get out of the area's they are intentionally trapped in. This happens to me 100% of the time with entities that are on a chunk border, and 0% of the time on non-borders. Specifically, they are clipping across 1 chunk to the other. I have not observed if this only happens in 1 direction, but it does happen on the N/S and E/W borders