// gradle.properties
org.gradle.daemon=true
org.gradle.configureondemand=true
org.gradle.jvmargs=-Xmx4g -XX:MaxPermSize=2048m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8

// app/build.gradle
dexOptions {
       javaMaxHeapSize "3g"
    }