get cpu archs only if there are suitable hosts

Author: Pearl1594

server/src/main/java/com/cloud/server/ManagementServerImpl.java

@@ -1614,9 +1614,11 @@ public Ternary<Pair<List<? extends Host>, Integer>, List<? extends Host>, Map<Ho
         }
 
         // Only list hosts of the same architecture as the source Host in a multi-arch zone
-        List<CPU.CPUArch> clusterArchs = ApiDBUtils.listZoneClustersArchs(vm.getDataCenterId());
-        if (CollectionUtils.isNotEmpty(clusterArchs) && clusterArchs.size() > 1 && !suitableHosts.isEmpty()) {
-            suitableHosts = suitableHosts.stream().filter(h -> h.getArch() == srcHost.getArch()).collect(Collectors.toList());
+        if (!suitableHosts.isEmpty()) {
+            List<CPU.CPUArch> clusterArchs = ApiDBUtils.listZoneClustersArchs(vm.getDataCenterId());
+            if (CollectionUtils.isNotEmpty(clusterArchs) && clusterArchs.size() > 1) {
+                suitableHosts = suitableHosts.stream().filter(h -> h.getArch() == srcHost.getArch()).collect(Collectors.toList());
+            }
         }
 
         return new Ternary<>(otherHosts, suitableHosts, requiresStorageMotion);