diff --git a/lib/classes/task/abstract.php b/lib/classes/task/abstract.php
index 365f9f1923..154f3de0d1 100644
--- a/lib/classes/task/abstract.php
+++ b/lib/classes/task/abstract.php
@@ -26,8 +26,10 @@ abstract class task_abstract
     const MINRECS = 10;
     const MAXRECS = 100;
     // default min/max values for the 'overflow memory (Mo)' setting on tasks
-    const MINMEGS = 20;
+    const MINMEGS = 64;
     const MAXMEGS = 256;
+    // default memory value
+    const DEFMEGS = 92;
     // default min/max values for the 'period (seconds)' setting on tasks
     const MINPERIOD = 10;
     const MAXPERIOD = 3600;
@@ -775,7 +777,7 @@ abstract class task_abstract
 
         $this->maxmegs = (integer) $sx_task_settings->maxmegs;
         if ($sx_task_settings->maxmegs < self::MINMEGS || $sx_task_settings->maxmegs > self::MAXMEGS) {
-            $this->maxmegs = self::MINMEGS;
+            $this->maxmegs = self::DEFMEGS;
         }
 
         $this->record_buffer_size = (integer) $sx_task_settings->flush;
diff --git a/lib/classes/task/period/subdef.php b/lib/classes/task/period/subdef.php
index 3bb096403b..e6b7da45d0 100644
--- a/lib/classes/task/period/subdef.php
+++ b/lib/classes/task/period/subdef.php
@@ -14,11 +14,7 @@ use MediaAlchemyst\Transmuter\Image2Image;
 
 class task_period_subdef extends task_databoxAbstract
 {
-    const MINMEGS = 20;
-    const MAXMEGS = 64;
-
     const MINFLUSH = 10;
-    const MAXFLUSH = 100;
 
     /**
      * Record buffer for writing meta datas after building subdefs
@@ -360,7 +356,7 @@ class task_period_subdef extends task_databoxAbstract
         $period = isset($params['period']) ? $params['period'] : self::MINPERIOD;
         $flush = isset($params['flush']) ? $params['flush'] : self::MINFLUSH;
         $maxrecs = isset($params['maxrecs']) ? $params['maxrecs'] : self::MINRECS;
-        $maxmegs = isset($params['maxmegs']) ? $params['maxmegs'] : self::MINMEGS;
+        $maxmegs = isset($params['maxmegs']) ? $params['maxmegs'] : self::DEFMEGS;
 
         return sprintf('<?xml version="1.0" encoding="UTF-8"?>
             <tasksettings>
diff --git a/lib/classes/task/period/writemeta.php b/lib/classes/task/period/writemeta.php
index 0bf40e9a6d..14f5e21f98 100644
--- a/lib/classes/task/period/writemeta.php
+++ b/lib/classes/task/period/writemeta.php
@@ -344,7 +344,7 @@ class task_period_writemeta extends task_databoxAbstract
     {
         $period = isset($params['period']) ? $params['period'] : self::MINPERIOD;
         $maxrecs = isset($params['maxrecs']) ? $params['maxrecs'] : self::MINRECS;
-        $maxmegs = isset($params['maxmegs']) ? $params['maxmegs'] : self::MINMEGS;
+        $maxmegs = isset($params['maxmegs']) ? $params['maxmegs'] : self::DEFMEGS;
 
         return sprintf('<?xml version="1.0" encoding="UTF-8"?>
             <tasksettings>