Your build hit the 4G memory limit in Android

Hi!
I use mockito and robolectric tests. To measure tests quality I use pitest. When I run gradlew pitest I get
Your build hit the 4G memory limit
even with this config
GRADLE_OPTS: ‘-Dorg.gradle.jvmargs="-Xmx2048m -XX:+HeapDumpOnOutOfMemoryError"’

Can someone help me with this? Thanks

Please see: https://circleci.com/docs/1.0/oom/#out-of-memory-errors-in-android-builds