<feature>[kvm]: make VM host file sync configurable

Add two global configs to control VM host file periodic
sync behavior. VM_HOST_FILE_SYNC_INTERVAL controls sync
frequency (default 1800 seconds) and
VM_HOST_FILE_SYNC_CONCURRENCY controls concurrent
sync operations (default 5).

Remove hardcoded constants and replace with configurable
values. Add GlobalConfigUpdateExtensionPoint listener
to restart tracker when configs change dynamically.
This provides flexibility for tuning performance.

Resolves: ZSV-11613
Related: ZSV-11310

Change-Id: I7273797a666a77617a72796f6e7a6b696373746f

Author: Zhang Wenhao

plugin/kvm/src/main/java/org/zstack/kvm/KVMGlobalConfig.java

@@ -166,4 +166,14 @@ public class KVMGlobalConfig {
             description = "Specify the EDK version to be used for the next VM startup. None indicates the use of the system's default EDK version")
     @BindResourceConfig(value = {VmInstanceVO.class, ClusterVO.class})
     public static GlobalConfig VM_EDK_VERSION_CONFIG = new GlobalConfig(CATEGORY, "vm.edk.version");
+
+    @GlobalConfigValidation(numberGreaterThan = 1, numberLessThan = 86400)
+    @GlobalConfigDef(defaultValue = "1800", type = Long.class,
+            description = "Interval in seconds for syncing VM host files (NvRam, TpmState) from KVM hosts")
+    public static GlobalConfig VM_HOST_FILE_SYNC_INTERVAL = new GlobalConfig(CATEGORY, "vm.host.file.sync.interval");
+
+    @GlobalConfigValidation(numberGreaterThan = 1, numberLessThan = 30)
+    @GlobalConfigDef(defaultValue = "5", type = Integer.class,
+            description = "The concurrency level for syncing VM host files from KVM hosts")
+    public static GlobalConfig VM_HOST_FILE_SYNC_CONCURRENCY = new GlobalConfig(CATEGORY, "vm.host.file.sync.concurrency");
 }

plugin/kvm/src/main/java/org/zstack/kvm/efi/VmHostFileTracker.java

@@ -6,6 +6,7 @@
 import org.zstack.core.cloudbus.CloudBus;
 import org.zstack.core.cloudbus.CloudBusCallBack;
 import org.zstack.core.cloudbus.ResourceDestinationMaker;
+import org.zstack.core.config.GlobalConfigUpdateExtensionPoint;
 import org.zstack.core.db.Q;
 import org.zstack.core.thread.PeriodicTask;
 import org.zstack.core.thread.ThreadFacade;
@@ -20,6 +21,7 @@
 import org.zstack.header.vm.additions.VmHostFileType;
 import org.zstack.header.vm.additions.VmHostFileVO;
 import org.zstack.header.vm.additions.VmHostFileVO_;
+import org.zstack.kvm.KVMGlobalConfig;
 import org.zstack.utils.Utils;
 import org.zstack.utils.logging.CLogger;
 
@@ -33,9 +35,6 @@
 public class VmHostFileTracker implements Component {
     private static final CLogger logger = Utils.getLogger(VmHostFileTracker.class);
 
-    private static final long SYNC_INTERVAL_SECONDS = TimeUnit.MINUTES.toSeconds(30);
-    private static final int SYNC_CONCURRENCY = 5;
-
     @Autowired
     private ThreadFacade threadFacade;
     @Autowired
@@ -52,6 +51,34 @@ public boolean start() {
             return true;
         }
 
+        submitTrackerTask();
+
+        GlobalConfigUpdateExtensionPoint listener = (oldConfig, newConfig) -> {
+            logger.debug(String.format("%s changed from %s to %s, restarting vm-host-file-tracker",
+                    newConfig.getCanonicalName(), oldConfig.value(), newConfig.value()));
+            submitTrackerTask();
+        };
+
+        KVMGlobalConfig.VM_HOST_FILE_SYNC_INTERVAL.installUpdateExtension(listener);
+        KVMGlobalConfig.VM_HOST_FILE_SYNC_CONCURRENCY.installUpdateExtension(listener);
+
+        return true;
+    }
+
+    @Override
+    public boolean stop() {
+        if (trackerThread != null) {
+            trackerThread.cancel(true);
+        }
+        return true;
+    }
+
+    private synchronized void submitTrackerTask() {
+        if (trackerThread != null) {
+            trackerThread.cancel(true);
+        }
+
+        long interval = KVMGlobalConfig.VM_HOST_FILE_SYNC_INTERVAL.value(Long.class);
         trackerThread = threadFacade.submitPeriodicTask(new PeriodicTask() {
             @Override
             public TimeUnit getTimeUnit() {
@@ -60,7 +87,7 @@ public TimeUnit getTimeUnit() {
 
             @Override
             public long getInterval() {
-                return SYNC_INTERVAL_SECONDS;
+                return interval;
             }
 
             @Override
@@ -74,16 +101,6 @@ public void run() {
                 syncVmHostFiles();
             }
         });
-
-        return true;
-    }
-
-    @Override
-    public boolean stop() {
-        if (trackerThread != null) {
-            trackerThread.cancel(true);
-        }
-        return true;
     }
 
     private void syncVmHostFiles() {
@@ -104,6 +121,8 @@ private void syncVmHostFiles() {
                 .collect(Collectors.groupingBy(f -> f.getVmInstanceUuid() + "::" + f.getHostUuid()));
         List<List<VmHostFileVO>> groups = new ArrayList<>(grouped.values());
 
+        int concurrency = KVMGlobalConfig.VM_HOST_FILE_SYNC_CONCURRENCY.value(Integer.class);
+
         new While<>(groups).step((group, whileCompletion) -> {
             VmHostFileVO first = group.get(0);
             String vmUuid = first.getVmInstanceUuid();
@@ -137,7 +156,7 @@ public void run(MessageReply reply) {
                     whileCompletion.done();
                 }
             });
-        }, SYNC_CONCURRENCY).run(new WhileDoneCompletion(null) {
+        }, concurrency).run(new WhileDoneCompletion(null) {
             @Override
             public void done(ErrorCodeList errorCodeList) {
                 // periodic sync round finished, empty callback