Unable to run gateway 11.x on Debian appliance with more than +/- 4350 threads e.a. . io.httpCoreConcurrency and io.httpMaxConcurrency set to above 4350 this worked on centos with gateway 10.x
The ssg logs shows a error like this while there is enough memory allocated to the Virtual Machine:
2023-10-20T13:39:45.665+0200 WARNING 1 com.l7tech.server.boot.GatewayMain: Error starting server : unable to create native thread: possibly out of memory or process/resource limits reached
Gateway 11.x on Debian OVA
On Debian there is a new limit which is imposed by way of the systemd "TasksMax" limit which sets pids.max on the cgroup.
For services the DefaultTasksMax default is 15% of the kernel limit pids_max (usually 4,915).
systemctl show --property DefaultTasksMax
You can override it for the service by setting TasksMax in "systemctl edit" or update DefaultTasksMax in /etc/systemd/system.conf
Setting DefaultTasksMax to 30% and a reboot allows you to run the gateway with around 10000 concurrent connections .
keep in mind there are other limits which impact if this works , ulimit max open files needs to be higher than 10000 too in this scenario.
We do not recommend to set io.httpCoreConcurrency and io.httpMaxConcurrency to anything above 1500 in general unless there is valid use case .
See also the documentation on this topic :