Your cloud provider may be doing it for you. Ops informed me one day that AWS was pushing out a critical security update to their host OS. So of course I asked if that meant I needed to redeploy our cluster, and they responded no, and in fact they had already pushed it.

Our cluster keeps stats on when processes start. So we can alert on crashes, and because new processes (cold JIT) can skew the response numbers, and are inflection points to analyze performance improvements or regressions. There were no restarts that morning. So they pulled the tablecloth out from under us. TIL.