diff --git a/biopet.wdl b/biopet.wdl
index cb3938dc36b260c0c8fd8641aac1c637a489b967..03b1a04eb91ee2888f060506bbc7de1b99d49428 100644
--- a/biopet.wdl
+++ b/biopet.wdl
@@ -62,7 +62,7 @@ task SampleConfig {
         set -e -o pipefail
         ${preCommand}
         mkdir -p . ${"$(dirname " + jsonOutputPath + ")"} ${"$(dirname " + tsvOutputPath + ")"}
-        java -Xmx4G -jar ${tool_jar} \
+        java -Xmx3G -jar ${tool_jar} \
         -i ${sep="-i " inputFiles} \
         ${"--sample " + sample} \
         ${"--library " + library} \