diff --git a/README.md b/README.md
index b6df7ec..f560ba2 100644
--- a/README.md
+++ b/README.md
@@ -123,7 +123,8 @@ Available `float` config options:
 * `vmPolicy`: the VM creation policy, specified as a map.  Refer to the CLI usage
               for the list of available options.
 * `timeFactor`: a float number.  default to 1.  An extra factor to multiply based 
-  on the time supplied by the task.  Use it to resolve some task timeouts.
+  on the time supplied by the task.  Add time factor to enlarge the default timeout of the task.  
+  Because WaveRider may take extra time for job migration.
 * `maxCpuFactor`: a float number.  default to 4.  The maximum CPU cores of the instance is set
   to `maxCpuFactor` * `cpus` of the task.
 * `maxMemoryFactor`: a float number.  default to 4.  The maximum memory of the instance is set
@@ -187,6 +188,7 @@ float {
     address = 'op.center.address'
     username = secrets.MMC_USERNAME
     password = secrets.MMC_PASSWORD
+    timeFactor = 2
 }
 
 aws {
diff --git a/plugins/nf-float/src/main/com/memverge/nextflow/FloatTaskHandler.groovy b/plugins/nf-float/src/main/com/memverge/nextflow/FloatTaskHandler.groovy
index c2f61cb..b6b6019 100644
--- a/plugins/nf-float/src/main/com/memverge/nextflow/FloatTaskHandler.groovy
+++ b/plugins/nf-float/src/main/com/memverge/nextflow/FloatTaskHandler.groovy
@@ -72,12 +72,15 @@ class FloatTaskHandler extends GridTaskHandler {
     @Override
     boolean checkIfCompleted() {
         final FloatStatus st =  floatExecutor.getJobStatus(task)
+        log.debug "got status ${st} for ${task.id} from float executor"
         if (st.finished) {
             status = COMPLETED
             task.exitStatus = readExitStatus()
             if (task.exitStatus == null) {
+                log.debug "can't get ${task.id} exit status from file system"
                 task.exitStatus = floatExecutor.getJobRC(task.id)
             }
+            log.debug "set ${task.id} exit status to ${task.exitStatus}"
             if (task.exitStatus == null) {
                 if (st.isError()) {
                     task.exitStatus = 1