APIcast Intermittently returns 404 errors due to Child Process Out-of-Memory kill

Issue

• API calls return 404 intermittently
• Backend API doesn't show calls failing

• APIcast logs show child killed and restarted

  [notice] 15#15: signal 17 (SIGCHLD) received from 3643
  [alert] 15#15: worker process 3643 exited on signal 9
  [notice] 15#15: start worker process 3644
  [notice] 15#15: signal 29 (SIGIO) received
  ...
  [warn] 3644#3644: *294728 errors.lua:52: get_upstream(): could not find service for host: api.apps.ocp.example.com, requestID=abcxyz...
  ...
  api-delete.apps.ocpprod.tndhs.local:8080 10.0.0.25:38864 "POST /apis/address HTTP/1.1" 404 5 (0.000) 0