Cache vim_performance_state relations

we were having trouble that the reverse relation (assoc.parent) was not being cached
Ended up deciding caching the forward and the reverse are the best

app/models/metric/ci_mixin/state_finders.rb

@@ -32,11 +32,17 @@ def preload_vim_performance_state_for_ts_iso8601(conditions = {})
     @states_by_ts = vim_performance_states.where(conditions).index_by { |x| x.timestamp.utc.iso8601 }
   end
 
+  # Use VimPerformanceState to populate the scopes with the values from a particular point in time
+  # using @last_vps_ts to ensure we don't load at one time and then use at another
   def vim_performance_state_association(ts, assoc)
     if assoc.to_s == "miq_regions"
       return respond_to?(:miq_regions) ? miq_regions : []
     end
 
-    vim_performance_state_for_ts(ts).public_send(assoc)
+    return send(assoc) if defined?(@last_vps_ts) && @last_vps_ts == ts
+
+    @last_vps_ts = ts
+    public_send(assoc).reset
+    vim_performance_state_for_ts(ts).public_send(assoc).tap { |scope| MiqPreloader.preload(self, assoc, scope) }
   end
 end