[MC-82945] UUID error: Tried to add entity with duplicate UUID spam

My log is spammed with these:
[16:05:17] [Server thread/WARN]: Tried to add entity with duplicate UUID c9904869-a99c-49eb-b746-b2b128f607b0

One way to reproduce

Build and turn on a nether portal.
Push a pig into the portal.
The pig disappeared and in the launcher there is the warning "Tried to add entity with duplicate UUID..."

It works with any entity that can teleport besides the player and with end and nether portals.

There might also be other situations in which this bug appears but this is one where it shouldn't for sure. To be clear: This deletes entities instead of porting them!

Possible reason for this bug

I assume that the reason this is happening, is that when entities are teleported to an other dimension they get duplicated and their clone is sent to the other dimension.

The cloned entity probably has the same UUID and therefore causes this problem.

Moderator node:

Also occuring without any portals, see comment

Confirmed in 15w31c. No portals at all. Plain survival on new world, no commands, no eggs. Heavy console spamming (4 to 8 errors/minute) causing significant server lags.

and MC-84645

I mean, like this:

[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 9ab31ebc-7c46-48bd-b544-427d4bc862a0
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 0daf1cc6-5dc4-4029-8365-90e7b31b67c3
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 7e8f3c03-e0a4-4827-90b9-74ef80799eeb
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 73f26e4c-1d4b-453c-94b5-840b6493bfa7
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 22e37536-a519-423d-aee7-ffaeb8c15c99
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID ce23a2c9-ed5d-4fa6-9fac-1eff3cde177b
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 72cb186a-9b82-4727-bfe2-0996aeda64b3
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 5735f2c2-0ed4-4247-af20-83add75f6734
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 9aa74053-a63e-437c-b423-a7043cb0a470
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 314fccd6-b476-4f80-b9ce-516dc80f7154
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 1cc80483-084b-4a7f-84fb-05b6ad0fda3c
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 18b6f6fc-de44-4f9e-9475-97a40fdff532
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID b8e2c921-7ead-4e1a-a5f6-bf5c9395993f
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 8b6b245f-5f16-48ce-9cc6-794c3d982283
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 2a4ea85d-5aab-42db-9a18-e99acafb4028
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID a33ea6b7-dc02-446d-a85e-5a7fbcae9c10
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 4bac6bac-ecbc-4a8b-9de3-fc4f08b361cf
[16:05:24] [Server thread/WARN]: Tried to add entity with duplicate UUID 2c53b3f6-9114-4e59-8a1d-e2cc028bdb45
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID b66bcfa4-fb50-4691-89ff-5add1db3bdcb
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID c52bc750-fb20-477d-8901-0f54aa2afc0d
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID d259f2cb-4070-403f-bcd2-823b2be1fca6
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID ebc8a4a0-5483-4a77-bc1b-02d3076590da
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID 4b8fb5f1-b085-4c14-8f7d-3f6031879181
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID 8f8a508c-dbbf-4d9b-888f-da9af3405718
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID e540eae6-5fb7-4fd1-8171-d09582cf9b7c
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID 6f96de8c-6c29-4a53-9d65-e36949b063e2
[16:05:31] [Server thread/WARN]: Tried to add entity with duplicate UUID 53bf038b-685e-4293-91c7-3806f5d212f7
[16:05:33] [Server thread/WARN]: Tried to add entity with duplicate UUID b04b6840-f6f3-4301-83cc-0f2992e7c30e
[16:05:33] [Server thread/WARN]: Tried to add entity with duplicate UUID 7739bad1-a3ca-4c02-b2f5-823f67e9fc7e
[16:05:33] [Server thread/WARN]: Tried to add entity with duplicate UUID 717a78b9-ab22-4908-8481-0c06f0ac5ea3

What is this?

Related issues

is duplicated by

MC-84079 Tried to add entity with duplicate UUID

MC-84165 Server upgrade from 1.8.x to 15w31b results in "duplicate UUID" error.

MC-84523 World generation and over-all tick lag

MC-84645 Multiplayer Lag

MC-84852 Extreme lag in mc 15w31c

MC-84868 Tried to add entity with duplicate UUID

MC-85328 tried to add entity (entity name) duplicate UUID (UUID string)

MC-85696 minecarts disappear

relates to

MC-83350 Entities teleporting through a portal disappear instead of teleporting.

MC-85285 Entities removed from world unless in mine carts

MC-87560 Possible spawning of entities with same UUID causes entity to not spawn

MC-88922 Console spam "Tried to add entity with pending removal and duplicate UUID"

Attachments

Comments

migrated 2015-07-29T14:30:17Z

[media]

migrated 2015-07-29T20:11:50Z

I got a spam of "Tried to add entity with duplicate UUID" too when I was spawning a bunch of Guardians from eggs to test. 15w31a

marcono1234 2015-07-30T13:09:29Z

This is to prevent multiple entities from having the same UUID, for example try using the following command twice:

/summon Pig ~ ~ ~ {UUIDLeast:0,UUIDMost:0}

Possible bug

However this message should definitely not appear so often! As the UUID is random chances that two entities with the same UUID exist should be way lower.

Possible problem

Currently it did not happen to me, but I am afraid that Minecraft might cancel a /summon command if it picks by random an already existing UUID. If so that might break many command block contraptions as this bug can't be handled or even prevented by the player.
Minecraft should keep trying summoning a mob if no explicit UUID is given.

Panda4994 2015-07-30T21:49:40Z

Way to reproduce

Build and turn on a nether portal.
Push a pig into the portal.
The pig disappeared and in the launcher there is the warning "Tried to add entity with duplicate UUID..."

It works with any entity that can teleport besides the player and with end and nether portals.

There might also be other situations in which this bug appears but this is one where it shouldn't for sure. To be clear: This deletes entities instead of porting them!

Possible reason for this bug

I assume that the reason this is happening, is that when entities are teleported to an other dimension they get duplicated and their clone is sent to the other dimension.

The cloned entity probably has the same UUID and therefore causes this problem.

migrated 2015-07-30T22:17:47Z

We are getting this error with out using any summon, eggs and or cheat commands. Just testing pure survival. I would imagine in our case it would be natural spawners causing the issue.
The issue is so frequent that it is causing poor server performance.

migrated 2015-07-31T13:18:15Z

I am getting this quite a lot for every player UUID on the sevrer console, which is anywhere from 20-40 players

Panda4994 2015-07-31T19:33:54Z

Can confirm for 14w31c using portals (see my previous comment). Can someone add that to the affected versions, add the steps to reproduce to the post and set it to confirmed, please 🙂

migrated 2015-07-31T21:23:39Z

Confirmed for 15w31c with portals as well. No commands.

EarlyReflections 2015-08-01T14:22:47Z

Confirmed in 15w31c. No portals at all. Plain survival on new world, no commands, no eggs. Heavy console spamming (4 to 8 errors/minute) causing significant server lags.

migrated 2015-08-04T20:47:45Z

I have this too from a 1.8 created world, and I assume it is responsible for making the fps go to 0, it was fine until c snapshot, now when I go to this area the fps drops to 0 or 1 and makes the game unplayable.

[21:14:06] [Client thread/INFO]: Setting user: 68firerock
[21:14:06] [Client thread/INFO]: (Session ID is token:<removed>)
[21:14:07] [Client thread/INFO]: LWJGL Version: 2.9.4
[21:14:08] [Client thread/INFO]: Reloading ResourceManager: Default
[21:14:08] [Sound Library Loader/INFO]: Starting up SoundSystem...
[21:14:08] [Thread-6/INFO]: Initializing LWJGL OpenAL
[21:14:08] [Thread-6/INFO]: (The LWJGL binding of OpenAL. For more information, see http://www.lwjgl.org)
[21:14:08] [Thread-6/INFO]: OpenAL initialized.
[21:14:09] [Sound Library Loader/INFO]: Sound engine started
[21:14:24] [Client thread/INFO]: Created: 512x512 textures-atlas
[21:14:53] [Server thread/INFO]: Starting integrated minecraft server version 15w31c
[21:14:53] [Server thread/INFO]: Generating keypair
[21:14:53] [Server thread/INFO]: Preparing start region for level 0
[21:14:54] [Server thread/WARN]: Tried to add entity with duplicate UUID 0108baaf-d163-477c-bc8e-7fab951aaedd
[21:14:54] [Server thread/INFO]: Preparing spawn area: 15%
[21:14:55] [Server thread/WARN]: Tried to add entity with duplicate UUID 5ee95e67-d6b4-45e5-b88b-08891a68aef5
[21:14:55] [Server thread/WARN]: Tried to add entity with duplicate UUID e9a1a6a8-972e-41a1-8369-595440b48e1a
[21:14:55] [Server thread/WARN]: Tried to add entity with duplicate UUID 099fb2ed-e7db-4238-a9b2-25aa9b2cfd15
[21:14:55] [Server thread/WARN]: Tried to add entity with duplicate UUID 938bfc5a-f0bf-4397-b173-e108df8720f6
[21:14:55] [Server thread/WARN]: Tried to add entity with duplicate UUID 48bc2ff8-66fe-4bda-9461-a5bf733dcb03
[21:14:55] [Server thread/WARN]: Tried to add entity with duplicate UUID b5f1d274-b860-415c-bc22-92bf2e4dc04d
[21:14:55] [Server thread/INFO]: Preparing spawn area: 74%
[21:14:57] [Server thread/INFO]: Changing view distance to 19, from 10
[21:14:57] [Server thread/INFO]: 68firerock[local:E:472a721d] logged in with entity id 348 at (-581.0954569328863, 72.0, 788.3282100706695)
[21:14:57] [Server thread/INFO]: 68firerock joined the game
[21:15:05] [Server thread/WARN]: Tried to add entity with duplicate UUID 7ea22c8e-43f2-4c45-bdba-48e5dac477a4
[21:15:10] [Server thread/WARN]: Can't keep up! Did the system time change, or is the server overloaded? Running 13424ms behind, skipping 268 tick(s)
[21:15:53] [Server thread/WARN]: Tried to add entity with duplicate UUID 5a38c839-0e45-4ae4-b66e-5c5e181d6b0a
[21:15:57] [Server thread/INFO]: Saving and pausing game...
[21:15:57] [Server thread/INFO]: Saving chunks for level '1.8 vill'/Overworld
[21:15:57] [Server thread/INFO]: Saving chunks for level '1.8 vill'/Nether
[21:15:57] [Server thread/INFO]: Saving chunks for level '1.8 vill'/The End
[21:16:00] [Chunk Batcher 1/WARN]: Needed to grow BufferBuilder buffer: Old size 524288 bytes, new size 2621440 bytes.
[21:16:10] [Chunk Batcher 0/WARN]: Needed to grow BufferBuilder buffer: Old size 524288 bytes, new size 2621440 bytes.
[21:16:42] [Server thread/INFO]: Saving and pausing game...
[21:16:42] [Server thread/INFO]: Saving chunks for level '1.8 vill'/Overworld
[21:16:43] [Server thread/INFO]: Saving chunks for level '1.8 vill'/Nether
[21:16:43] [Server thread/INFO]: Saving chunks for level '1.8 vill'/The End
[21:16:50] [Chunk Batcher 1/WARN]: Needed to grow BufferBuilder buffer: Old size 524288 bytes, new size 2621440 bytes.

migrated 2015-08-04T21:24:14Z

file shot showing 1fps, it seems to be facing south, facing north it doesn't happen

migrated 2015-08-05T09:43:05Z

thnaks, removed

migrated 2015-08-05T15:37:03Z

[15:53:08] [Server thread/INFO]: GrouchyOldMan joined the game
[15:56:52] [Server thread/WARN]: Tried to add entity Creeper with duplicate UUID bf84f1bb-16ad-41b4-8bb0-9c02758263e0
[15:56:52] [Server thread/WARN]: Tried to add entity Creeper with duplicate UUID cfb697d6-2dcc-41a1-8fb7-1109b04d47b7
[15:56:52] [Server thread/WARN]: Tried to add entity Bat with duplicate UUID b4a62b7c-a40e-4d6f-9cba-86c9fbd1a3db

Still present in 15W32a. Fresh world created in this snapshot and suffering the same huge drops in FPS.

[16:35:23 INFO]: Minecraft Launcher 1.6.13 (through bootstrap 4) started on linux...
[16:35:23 INFO]: Current time is Aug 5, 2015 4:35:23 PM
[16:35:23 INFO]: System.getProperty('os.name') == 'Linux'
[16:35:23 INFO]: System.getProperty('os.version') == '3.19.0-25-generic'
[16:35:23 INFO]: System.getProperty('os.arch') == 'amd64'
[16:35:23 INFO]: System.getProperty('java.version') == '1.8.0_45-internal'
[16:35:23 INFO]: System.getProperty('java.vendor') == 'Oracle Corporation'
[16:35:23 INFO]: System.getProperty('sun.arch.data.model') == '64'
[16:35:23 INFO]: proxy == DIRECT
[16:35:23 INFO]: Refreshing local version list...
[16:35:23 INFO]: Refreshing remote version list...
[16:35:24 INFO]: Refresh complete.
[16:35:24 INFO]: Loaded 5 profile(s); selected 'testing'
[16:35:24 INFO]: Refreshing auth...
[16:35:24 INFO]: Logging in with access token

EarlyReflections 2015-08-05T19:55:06Z

It's even worse in 15w32a. Animals just keep vanishing everywhere. Impossible to keep them in a pen. Everyone on my server lost their animals. Animals in the wild don't seem to be affected, which is kinda weird.

migrated 2015-08-06T12:50:34Z

Had over 100 animals (Cows, Pigs, Chickens and 2 horses) in a pen, now they're all gone. (I get the same error spamed to my server console too)(15w32a)

migrated 2015-08-06T15:01:04Z

This appears to be fixed for the Exit End Portal in the end, only. The nether portals, and the entrance portal to the End is still broken with this bug.

migrated 2015-08-06T15:20:03Z

Still occurring for me in 15w32b. It seems to be caused by poppies entering the Nether from my Iron Titan. The poppies never arrive so the chunks will unload as soon as you leave them and break the farm.

migrated 2015-08-06T18:41:42Z

Just started up a new world on my 15w32b server, no noticeable lag at first, but getting the message spammed in my console.

The two that show up are FallingSand and MinecartChest entities

[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 58e6ada9-d8a9-4daa-bed3-32ce3a7d3355
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 63ffed57-5e26-4382-bb9a-3ac47b68d301
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 6ba27c29-13c9-4067-8e15-5e2f99f8a128
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID d04f593d-8e47-4c4d-8fb8-1a54aa35ce49
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 7938ce7f-e092-4e39-aa61-2f5362dbcf12
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 16df3116-3a2a-4825-bdd1-bc7fbfae2982
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID bb5008c3-b273-4cf6-be43-3c51bde93699
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 6d37871f-0633-4cf2-9d69-9bf0a385f1bf
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 73beb5b9-50dd-445d-aafc-a47d5f238d81
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID f7505a4f-de8e-43da-8304-6661127c06e4
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 81800bfe-8884-4db9-850d-7ecd34b2d10f
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID ea839064-1e5a-438b-8f60-ad53cd30db17
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID dd83a441-4ac0-4741-982a-d7eccc620b1a
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID 7194809a-9cf4-41dc-b2e5-0d1f5c5e8234
[11:33:52 WARN]: Tried to add entity FallingSand with duplicate UUID ec6dd510-9f0d-46d2-9005-f351d78c1a1d

migrated 2015-08-06T18:52:31Z

The warning appears to happen periodically as I move around the world (nothing changing dimensions required), However sometimes as our spawn town loads and unloads many such messages appear, and as mentioned by Žilvinas the passive mobs in the area appear to despawn.

On 15w32a yesterday both our cows and chickens in addition to a randomly pig trapped near us despawned. today 15w32b the ckikens did after many messages such as:
[17:57:18] [Server thread/WARN]: Tried to add entity Chicken with duplicate UUID f57f94b0-d2ef-4b8e-86c1-edadbf33c3f3

Greener 2015-08-06T19:02:36Z

Yup, this just happened to some poor pigs. Affects 15w32b

migrated 2015-08-06T20:27:41Z

06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Item with duplicate UUID e69f6aa9-ba25-49ff-b28f-0ddfec08d542
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Item with duplicate UUID efdccc8f-b4e5-4779-a143-ed0e2f7d23e7
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Chicken with duplicate UUID 4e695419-cae2-4274-be02-f6fa3ef806ac
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Chicken with duplicate UUID 6c313677-0424-4d01-9a82-6be437496636
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Rabbit with duplicate UUID 9e9876b1-f394-4b7f-9136-9ab422457c18
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 2c3d8e70-debb-4612-a597-af1dad45853c
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID ee08c8dc-113f-4649-ae76-629ce75e91b7
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 237dda03-0a8f-4296-823f-2038e57edff8
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 728c0ca6-9241-4194-abf3-8471072144c7
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 10527b03-b251-4217-b5fa-4f3adade2695
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Rabbit with duplicate UUID 7dfaee19-ab3b-45da-b853-523084099177
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Rabbit with duplicate UUID 4f700591-9235-4069-8265-407e329a463f
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID e7019d97-741e-4fa3-aac2-d5b2e7e1b1c2
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID f0d71b47-bf49-467c-82a4-7221979485e8
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Pig with duplicate UUID 44378cea-61e5-4723-9df6-6a03d6091934
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Pig with duplicate UUID 9a343242-a827-4f4e-9d7f-491d8aff04e8
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Pig with duplicate UUID ac5013a3-7027-4003-9e85-13d765c4dc21
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 285de3c0-40ff-4ff7-9a01-fbe092836705
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 1b58c689-dcac-495e-a4fb-689e7baacf0b
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID bb2aad5e-ae31-4685-b09a-c8dc6795ad01
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 91ee16b9-6a64-4b3f-aa3a-445f0dd99010
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID da36401f-73ee-4051-981b-2f249d4955f1
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID ebe72613-13ee-433b-9b6c-afbf6d351731
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Rabbit with duplicate UUID 38df1029-d8b0-4a7b-bd55-0371e142186d
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID c257644e-2bad-4da1-9592-904de03647b2
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID 44c74315-1928-407a-b2eb-504b788691f0
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Sheep with duplicate UUID d85f2315-1435-4503-8336-77a65af935ca
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Item with duplicate UUID ec9d06e1-84a6-485a-b0a4-2c3ca5378e69
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Chicken with duplicate UUID d782bb1d-feb4-40a9-9ac0-10543ab3f2bd
06.08 16:29:09 [Server] INFO [16:29:09] [Server thread/WARN]: Tried to add entity Chicken with duplicate UUID 3200195d-d506-4d3c-9e84-1ab44f684230
06.08 16:28:51 [Server] INFO [16:28:51] [Server thread/WARN]: Tried to add entity Rabbit with duplicate UUID 59413c20-292a-401b-82f7-b93c09928e82

migrated 2015-08-07T13:12:15Z

Spamming affects 15w32b too. And after the upgrade from 15w32a many animals and ArmorStands (entitys general, i think) disappeared.

Greener 2015-08-07T15:34:13Z

This is also present in 15w32c

migrated 2015-08-07T19:52:09Z

15w32c is also affectet but on my Server the message doesnt appears so often. Now theres often a Spam with "[Server thread/WARN]: There were X entity removals pending!". Is that a Bag or 'normal'?

EarlyReflections 2015-08-07T23:49:27Z

15w32c seems to be a temporary fix for the vanishing entities. Console still spams with errors but different ones. Instead of being removed, entity removal remains "pending". It's a welcome semi-fix, now we can farm!

migrated 2015-08-09T09:41:10Z

My dogs disappeared! I think, Minecraft spawned another entities with the same UUID-es as my wolfs, and my wolfes disappeared!!!!!!

migrated 2015-08-11T20:59:01Z

In 15w32c the "Tried to add entity..." message no longer occurs. Now the server log is being spammed with "[Server thread/WARN]: There were X entity removals pending!". So far I haven't experienced any issues with animals or other entities disappearing. Except when breaking item frames – that causes both the frame and it's contents to vanish.

EarlyReflections 2015-08-13T05:58:54Z

Issue shouldn't be marked as fixed as it's only partially fixed, as of 15w33b. Entities are no longer removed (esp. animals) and console in no longer spamming "duplicate UUID" errors. But the issue about entities going through nether portals still exists. Nether portals simply destroy anything going through them, except for players.

kumasasa 2015-08-13T06:14:38Z

@@unknown: That's MC-83350

migrated 2015-09-20T15:16:55Z

This seems to still be an issue in 15w38b -

16:15:08 [Warn] Tried to add entity Sheep with pending removal and duplicate UUID 68fc04db-dcb0-4f38-8933-4587b4daa592
16:15:08 [Warn] Tried to add entity Item with pending removal and duplicate UUID 6c31ccf8-ec71-4c1b-99c9-e15fdef23004
16:15:08 [Warn] Tried to add entity Item with pending removal and duplicate UUID ad8010f0-1fc1-4a42-a8d4-63e7a1841122
16:15:08 [Warn] Tried to add entity Endermite with pending removal and duplicate UUID f80e8dcd-1d90-4dd5-9f39-5bbde311b52d
16:15:08 [Warn] Tried to add entity MinecartRideable with pending removal and duplicate UUID ca547f47-8b58-4d61-9b7b-af878b0bfc3b
16:15:08 [Warn] Tried to add entity Sheep with pending removal and duplicate UUID 68fc04db-dcb0-4f38-8933-4587b4daa592
16:15:08 [Warn] Tried to add entity Item with pending removal and duplicate UUID 6c31ccf8-ec71-4c1b-99c9-e15fdef23004
16:15:08 [Warn] Tried to add entity Item with pending removal and duplicate UUID ad8010f0-1fc1-4a42-a8d4-63e7a1841122
16:15:08 [Warn] Tried to add entity Endermite with pending removal and duplicate UUID f80e8dcd-1d90-4dd5-9f39-5bbde311b52d
16:15:08 [Warn] Tried to add entity MinecartRideable with pending removal and duplicate UUID ca547f47-8b58-4d61-9b7b-af878b0bfc3b

Had some weird issues with minecart chests duplication the contents onto the floor too.
The above section of the console log is with no one online.

migrated 2015-09-20T15:38:27Z

Sion, that's a seperate issue (MC-88922).

migrated 2015-10-17T15:32:08Z

How do we get this issue reopened? I'm having severe server lag in 1G memory, no more than four players at a time, even NO players my console is still getting spammed. This snip is just after a "boot after crash":

17.10 10:29:54 [Server] Server thread/WARN Tried to add entity Item with pending removal and duplicate UUID edf35989-60ca-4d45-ade1-29a197a04f4d
17.10 10:29:00 [Server] Server thread/WARN Can't keep up! Did the system time change, or is the server overloaded? Running 2772ms behind, skipping 55 tick(s)

We have a minimal redstone, the world simply isn't that big. This is a show-stopper bug in my opinion. How do we reopen this report?

Version: 15w42a, had the same issue from 15w41b

Oh, looks like this one and MC-88922 are related, I'm not sure which one is the correct one to follow. My issue isn't the "spam being reported in logs", my concern is the fundamental error being reported causing the tick lag. I want to stop the "spam" by NOT having my server confused to the point of crashing.

migrated 2015-10-17T16:18:04Z

@unknown: You'll want to create a separate ticket for that.

migrated 2015-11-17T02:16:11Z

Problem is not fixed. 15w46a still doing the UUID/ Dup spam

[18:04:20] [Server thread/WARN]: Tried to add entity Creeper with pending removal and duplicate UUID c387e1c1-c968-4e35-988f-9b62ea6dc35a
[18:04:20] [Server thread/WARN]: Tried to add entity Spider with pending removal and duplicate UUID ed561282-6b30-43ce-aa54-ea7252d4b1cc
[18:04:22] [Server thread/INFO]: Lloops lost connection: TextComponent{text='Disconnected', siblings=[], style=Style{hasParent=false, color=null, bold=null, italic=null, underlined=null, obfuscated=null, clickEvent=null, hoverEvent=null, insertion=null}}
[18:04:22] [Server thread/INFO]: §aLloops§r left the game
[18:04:23] [Server thread/WARN]: Tried to add entity MinecartRideable with pending removal and duplicate UUID 163c4cd0-3a7b-42f8-b7c7-aaa425f1c63c
[18:04:23] [Server thread/WARN]: Tried to add entity ItemFrame with pending removal and duplicate UUID 84ca08c0-d5e9-4016-a50e-1e498df0769d
[18:04:23] [Server thread/WARN]: Tried to add entity ItemFrame with pending removal and duplicate UUID a338e2ec-a412-45bb-923a-bdae9d388251
[18:04:23] [Server thread/WARN]: Tried to add entity MinecartRideable with pending removal and duplicate UUID 0006e693-01de-4023-8ecc-da092bd457ce
[18:04:23] [Server thread/WARN]: Tried to add entity Villager with pending removal and duplicate UUID 71dd305f-3eca-4e34-bc59-43e038507fb0
[18:04:23] [Server thread/WARN]: Tried to add entity MinecartRideable with pending removal and duplicate UUID 9bb69cde-d74a-4b5f-bbf8-c98eb1f90c7a
[18:04:23] [Server thread/WARN]: Tried to add entity Villager with pending removal and duplicate UUID f8d93fe3-2a70-49c4-b808-844775616289
[18:05:05] [Server thread/WARN]: Tried to add entity MinecartRideable with pending removal and duplicate UUID 163c4cd0-3a7b-42f8-b7c7-aaa425f1c63c
[18:05:05] [Server thread/WARN]: Tried to add entity ItemFrame with pending removal and duplicate UUID 84ca08c0-d5e9-4016-a50e-1e498df0769d
[18:05:05] [Server thread/WARN]: Tried to add entity ItemFrame with pending removal and duplicate UUID a338e2ec-a412-45bb-923a-bdae9d388251
[18:05:05] [Server thread/WARN]: Tried to add entity MinecartRideable with pending removal and duplicate UUID 0006e693-01de-4023-8ecc-da092bd457ce
[18:05:05] [Server thread/WARN]: Tried to add entity Villager with pending removal and duplicate UUID 71dd305f-3eca-4e34-bc59-43e038507fb0
[18:05:05] [Server thread/WARN]: Tried to add entity MinecartRideable with pending removal and duplicate UUID 9bb69cde-d74a-4b5f-bbf8-c98eb1f90c7a
[18:05:05] [Server thread/WARN]: Tried to add entity Villager with pending removal and duplicate UUID f8d93fe3-2a70-49c4-b808-844775616289

migrated 2015-11-17T09:47:33Z

"Pending removal and duplicate UUID" is MC-88922.

migrated 2015-12-15T04:53:06Z

I am still getting the "Tried to add entity" and "player moved too quickly" console messages very very frequently in 15w50a. Can this be re-opened?

migrated 2015-12-15T06:47:54Z

I agree, there must be something going wrong if these messages appear, I'll ask this then: could you at least make sure these messages don't show up in the full release?

migrated 2015-12-30T14:27:40Z

This is happening in my 1.8.8 - is there any fix - i removed all plugins - it still happened - though not when i used the normal server launcher - only when i used a start.bat file and run it off spigot

kumasasa 2015-12-30T14:31:33Z

@unknown, this issue is fixed in 1.9

migrated 2015-12-30T21:40:53Z

Are you saying that 1.9 release this has been fixed?

[Mod] Neko 2015-12-30T21:44:27Z

Yes. Updating to a version higher than 15w33a (or the release of 1.9), this bug will be fixed.

Skylinerw 2015-12-31T03:46:37Z

@@unknown This error was only present for a brief time during the 1.9 snapshots, it was not present in 1.8 at all. Do not report bugs to this tracker based on mods; this tracker is for vanilla.

migrated 2015-12-31T11:32:30Z

Is a plugin a mod?

kumasasa 2015-12-31T11:37:08Z

Yes.

migrated 2016-01-01T11:24:12Z

@Ender Dragon ... I can assure you at this stage the issues remains in the latest snapshot, so can only hope that it is indeed removed in 1.9 Release

migrated 2016-01-01T12:08:11Z

Warren Liddell, I can not confirm it's back, please provide the log

migrated 2016-01-01T12:17:32Z

Look up -lots of people reported it still present in updates past 15w33a

migrated 2016-01-01T14:31:45Z

looked on the tracker quickly, saw no reports past 15w33a, give an example

my server is not having this issue at all anymore

if you mean "Tried to add entity with pending removal and duplicate UUID" that's MC-88922 and was a debug message for the code that @unknown wrote to fix this

douira 2016-04-08T10:55:31Z

I still get this issue on a 1.9.2 server: (Is this another bug or the same one ?)
[15:35:35] [Server thread/WARN]: Keeping entity Zombie that already exists with UUID 4b8f8373-7dcf-4863-97b7-b970749d8da3
[15:35:35] [Server thread/WARN]: Keeping entity Zombie that already exists with UUID 39332185-ef35-44b6-b052-29746acacac3
[15:35:35] [Server thread/WARN]: Keeping entity Enderman that already exists with UUID 3c3fa926-1e41-4a22-ba32-c63d24b71954
[15:35:35] [Server thread/WARN]: Keeping entity Pig that already exists with UUID 25985b03-21a5-4e9a-8ea2-4e37f59aa08a
[15:35:35] [Server thread/WARN]: Keeping entity Bat that already exists with UUID 149bb2ca-cd28-4349-9c5a-6a54765b9cca

migrated 2016-04-08T11:57:18Z

that's MC-95649