diff --git a/public/biopet-extensions/src/main/scala/nl/lumc/sasc/biopet/extensions/varscan/VarscanMpileup2cns.scala b/public/biopet-extensions/src/main/scala/nl/lumc/sasc/biopet/extensions/varscan/VarscanMpileup2cns.scala
index 9dc5b91a8dc7adc9fa7dfc7a241d0de838563ede..085b1bc37031fbf1ef99bd8448dbcba6fc0d07a8 100644
--- a/public/biopet-extensions/src/main/scala/nl/lumc/sasc/biopet/extensions/varscan/VarscanMpileup2cns.scala
+++ b/public/biopet-extensions/src/main/scala/nl/lumc/sasc/biopet/extensions/varscan/VarscanMpileup2cns.scala
@@ -39,6 +39,8 @@ class VarscanMpileup2cns(val root: Configurable) extends Varscan {
   var vcfSampleList: Option[File] = config("vcf_sample_list")
   var variants: Option[Int] = config("variants")
 
+  override def defaultCoreMemory = 6.0
+
   override def beforeGraph(): Unit = {
     val validValues: Set[Int] = Set(0, 1)
     // check for boolean vars that are passed as ints