diff --git a/dataforge-core/src/main/kotlin/hep/dataforge/context/PluginLoader.kt b/dataforge-core/src/main/kotlin/hep/dataforge/context/PluginLoader.kt
index c1c7a40..d22a1db 100644
--- a/dataforge-core/src/main/kotlin/hep/dataforge/context/PluginLoader.kt
+++ b/dataforge-core/src/main/kotlin/hep/dataforge/context/PluginLoader.kt
@@ -120,7 +120,7 @@ abstract class AbstractPluginLoader : PluginLoader {
 
 
     protected fun compare(p1: PluginFactory, p2: PluginFactory): Int {
-        return Integer.compare(p1.tag.getInt("priority", 0), p2.tag.getInt("priority", 0))
+        return p1.tag.getInt("priority", 0).compareTo(p2.tag.getInt("priority", 0))
     }
 
     override fun listTags(): List<PluginTag> {
diff --git a/numass-viewer/build.gradle.kts b/numass-viewer/build.gradle.kts
index 29d5320..ca939a0 100644
--- a/numass-viewer/build.gradle.kts
+++ b/numass-viewer/build.gradle.kts
@@ -19,7 +19,7 @@ application {
     mainClass.set("inr.numass.viewer.Viewer")
 }
 
-version = "0.6.0"
+version = "0.6.1"
 
 description = "The viewer for numass data"
 
diff --git a/numass-viewer/src/main/kotlin/inr/numass/viewer/DataController.kt b/numass-viewer/src/main/kotlin/inr/numass/viewer/DataController.kt
index 891142e..9440566 100644
--- a/numass-viewer/src/main/kotlin/inr/numass/viewer/DataController.kt
+++ b/numass-viewer/src/main/kotlin/inr/numass/viewer/DataController.kt
@@ -41,15 +41,15 @@ class DataController : Controller(), ContextAware {
 
         val meta = point.meta
 
-        val channelSpectra: Deferred<Map<Int, Table>> = context.async(Dispatchers.IO) {
+        val channelSpectra: Deferred<Map<Int, Table>> = context.async {
             point.channels.mapValues { (_, value) -> analyzer.getAmplitudeSpectrum(value) }
         }
 
-        val spectrum: Deferred<Table> = context.async(Dispatchers.IO) {
+        val spectrum: Deferred<Table> = context.async{
             analyzer.getAmplitudeSpectrum(point)
         }
 
-        val timeSpectrum: Deferred<Table> = context.async(Dispatchers.IO) {
+        val timeSpectrum: Deferred<Table> = context.async{
             val cr = spectrum.await().sumOf {
                 it.getValue(NumassAnalyzer.COUNT_KEY).int
             }.toDouble() / point.length.toMillis() * 1000
@@ -117,7 +117,7 @@ class DataController : Controller(), ContextAware {
                         }
                     }
                 val watcher = watchPath.fileSystem.newWatchService()
-                watchJob = app.context.launch(Dispatchers.IO) {
+                watchJob = app.context.launch {
                     watcher.use { watcher ->
                         val key: WatchKey = watchPath.register(watcher,
                             StandardWatchEventKinds.ENTRY_CREATE)
diff --git a/numass-viewer/src/main/kotlin/inr/numass/viewer/HVView.kt b/numass-viewer/src/main/kotlin/inr/numass/viewer/HVView.kt
index 2ffece4..811f45e 100644
--- a/numass-viewer/src/main/kotlin/inr/numass/viewer/HVView.kt
+++ b/numass-viewer/src/main/kotlin/inr/numass/viewer/HVView.kt
@@ -55,7 +55,7 @@ class HVView : View(title = "High voltage time plot", icon = ImageView(dfIcon))
             }
             if (change.wasAdded()) {
                 runLater { container.progress = -1.0 }
-                runGoal(app.context,"hvData[${change.key}]", Dispatchers.IO) {
+                runGoal(app.context,"hvData[${change.key}]") {
                     change.valueAdded.getHvData()
                 } ui { table ->
                     if (table != null) {
diff --git a/numass-viewer/src/main/kotlin/inr/numass/viewer/MainView.kt b/numass-viewer/src/main/kotlin/inr/numass/viewer/MainView.kt
index be9d39d..93de7b6 100644
--- a/numass-viewer/src/main/kotlin/inr/numass/viewer/MainView.kt
+++ b/numass-viewer/src/main/kotlin/inr/numass/viewer/MainView.kt
@@ -61,7 +61,7 @@ class MainView : View(title = "Numass viewer", icon = dfIconView) {
             }
             if (Files.exists(path.resolve(NumassDataLoader.META_FRAGMENT_NAME))) {
                 //build set view
-                runGoal(app.context, "viewer.load.set[$path]", Dispatchers.IO) {
+                runGoal(app.context, "viewer.load.set[$path]") {
                     title = "Load set ($path)"
                     message = "Building numass set..."
                     NumassDataLoader(app.context, null, path.fileName.toString(), path)
diff --git a/numass-viewer/src/main/kotlin/inr/numass/viewer/SlowControlView.kt b/numass-viewer/src/main/kotlin/inr/numass/viewer/SlowControlView.kt
index 751e3b6..d6d8d9d 100644
--- a/numass-viewer/src/main/kotlin/inr/numass/viewer/SlowControlView.kt
+++ b/numass-viewer/src/main/kotlin/inr/numass/viewer/SlowControlView.kt
@@ -43,7 +43,7 @@ class SlowControlView : View(title = "Numass slow control view", icon = ImageVie
                 plot.remove(change.key)
             }
             if (change.wasAdded()) {
-                runGoal(app.context,"loadTable[${change.key}]", Dispatchers.IO) {
+                runGoal(app.context,"loadTable[${change.key}]") {
                     val plotData = change.valueAdded.asTable().await()
                     val names = plotData.format.namesAsArray().filter { it != "timestamp" }
 
diff --git a/numass-viewer/src/main/kotlin/inr/numass/viewer/Viewer.kt b/numass-viewer/src/main/kotlin/inr/numass/viewer/Viewer.kt
index ca1ad6b..a59533e 100644
--- a/numass-viewer/src/main/kotlin/inr/numass/viewer/Viewer.kt
+++ b/numass-viewer/src/main/kotlin/inr/numass/viewer/Viewer.kt
@@ -8,6 +8,7 @@ import hep.dataforge.fx.dfIcon
 import javafx.stage.Stage
 import org.slf4j.LoggerFactory
 import tornadofx.*
+import kotlin.system.exitProcess
 
 /**
  * Created by darksnake on 14-Apr-17.
@@ -28,6 +29,7 @@ class Viewer : App(MainView::class) {
         context.close()
         Global.terminate();
         super.stop()
+        exitProcess(0)
     }
 }