The service crashes with kill without visible errors — how to diagnose?

If a service crashes with a kill signal without visible errors, you should:

1. Check which specific signal the process receives (e.g., SIGKILL, SIGTERM).
2. Look at system and application logs for messages before the crash.
3. Use monitoring tools (e.g., top, htop, dmesg) to identify causes — possibly the system kills the process due to lack of memory (OOM killer).
4. Run the service with additional logging or in debug mode.
5. Check environment settings and resource limits (ulimit).

Example: if the process receives SIGKILL from the OOM killer, there will be a record in dmesg about the process termination due to lack of memory.