Downloaded the newest version of the server.jar and installed the correct java version.

However, I get this when I try to start it:

[14:14:21] [main/INFO]: Environment: authHost='https://authserver.mojang.com', accountsHost='https://api.mojang.com', sessionHost='https://sessionserver.mojang.com', servicesHost='https://api.minecraftservices.com', name='PROD'
[14:14:22] [main/WARN]: Ambiguity between arguments [teleport, location] and [teleport, destination] with inputs: [0.1 -0.5 .9, 0 0 0]
[14:14:22] [main/WARN]: Ambiguity between arguments [teleport, location] and [teleport, targets] with inputs: [0.1 -0.5 .9, 0 0 0]
[14:14:22] [main/WARN]: Ambiguity between arguments [teleport, destination] and [teleport, targets] with inputs: [Player, 0123, @e, dd12be42-52a9-4a91-a8a1-11c01849e498]
[14:14:22] [main/WARN]: Ambiguity between arguments [teleport, targets] and [teleport, destination] with inputs: [Player, 0123, dd12be42-52a9-4a91-a8a1-11c01849e498]
[14:14:22] [main/WARN]: Ambiguity between arguments [teleport, targets, location] and [teleport, targets, destination] with inputs: [0.1 -0.5 .9, 0 0 0]
[14:14:22] [main/INFO]: Reloading ResourceManager: Default
[14:14:23] [Worker-Main-4/INFO]: Loaded 7 recipes
[14:14:24] [Worker-Main-4/INFO]: Loaded 1109 advancements
[14:14:26] [Server thread/INFO]: Starting minecraft server version 21w19a
[14:14:26] [Server thread/INFO]: Loading properties
[14:14:26] [Server thread/INFO]: Default game type: SURVIVAL
[14:14:26] [Server thread/INFO]: Generating keypair
[14:14:26] [Server thread/INFO]: Starting Minecraft server on *:25565
[14:14:27] [Server thread/INFO]: Using epoll channel type
Mai 13, 2021 2:14:27 PM io.netty.util.internal.MacAddressUtil defaultMachineId
WARNING: Failed to find a usable hardware address from the network interfaces; using random bytes: d4:db:c6:8b:30:04:bd:32
[14:14:27] [Server thread/INFO]: Preparing level "world"
[15,434s][warning][os,thread] Failed to start thread - pthread_create failed (EAGAIN) for attributes: stacksize: 1024k, guardsize: 0k, detached.
[15,435s][warning][os,thread] Failed to start thread - pthread_create failed (EAGAIN) for attributes: stacksize: 1024k, guardsize: 0k, detached.
[14:14:28] [IO-Worker-7/ERROR]: Caught exception in thread Thread[IO-Worker-7,5,main]
java.lang.OutOfMemoryError: unable to create native thread: possibly out of memory or process/resource limits reached
{{ at java.lang.Thread.start0(Native Method) ~[?:?]}}
{{ at java.lang.Thread.start(Thread.java:800) ~[?:?]}}
{{ at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:939) ~[?:?]}}
{{ at java.util.concurrent.ThreadPoolExecutor.processWorkerExit(ThreadPoolExecutor.java:1007) ~[?:?]}}
{{ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) ~[?:?]}}
{{ at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630) ~[?:?]}}
{{ at java.lang.Thread.run(Thread.java:831) [?:?]}}
[74,514s][warning][os,thread] Failed to start thread - pthread_create failed (EAGAIN) for attributes: stacksize: 1024k, guardsize: 0k, detached.

Java version:

java version "16.0.1" 2021-04-20
Java(TM) SE Runtime Environment (build 16.0.1+9-24)
Java HotSpot(TM) 64-Bit Server VM (build 16.0.1+9-24, mixed mode, sharing)

EDIT:

Server HW:

CPU: Intel Xeon Silver 4116 (4) @ 1.999GHz

Memory: 123MiB / 8192MiB