How does Spring Boot behave when the JVM experiences CPU starvation at the OS level?

CPU starvation at OS level slows all Spring threads regardless of application logic.

When the OS scheduler cannot allocate CPU time fairly (due to throttling, noisy neighbors, or container limits), JVM threads are not executed efficiently. Spring Boot appears slow, but internally it is just waiting for CPU time. This leads to request latency spikes, timeouts, and thread pileups in Tomcat or Netty.