OutOfMemoryError: unable to create new native thread on Debian 10 backports

Hi all,

I'm trying to deploy Debian workloads on K8s clusters.

There was no issue so far, but recently after rollout on one staging env we faced OutOfMemoryError issue for an application. I have tried comparing the ulimit values with Amazon Linux2 and configured the same on my Debian AMI but not able to resolve this issue.

Please find the error message from the application below:

2022-12-19 07:23:42 java.lang.OutOfMemoryError: unable to create new native thread
2022-12-19 07:23:42,713 WARN [Timer-Driven Process Thread-19] o.a.n.controller.tasks.ConnectableTask Administratively Yielding FieldMapperProcessor[id=ecd6ab3e-0f4b-3c37-83dc-62fb38f40410]
due to uncaught Exception: java.lang.OutOfMemoryError: unable to create new native thread

I'm suspecting the max user process ulimit on the machine but updating that to unlimited didn't solve the issue.

OS Details:

uname -a ==>
Linux ip-x-x-x-x 5.10.0-0.deb10.19-cloud-amd64 #1 SMP Debian 5.10.149-2~deb10u1 (2022-10-28) x86_64

cat /etc/debian_version ==>
10.13 (final update of buster release)

Let me know if additional details are required.

Help is much appreciated