diff --git a/vtk.spec b/vtk.spec
index 6a3ff4b..6094c3b 100644
--- a/vtk.spec
+++ b/vtk.spec
@@ -588,11 +588,11 @@ export CXXFLAGS="%{optflags} -D_UNICODE -DHAVE_UINTPTR_T"
 export CPPFLAGS=-DACCEPT_USE_OF_DEPRECATED_PROJ_API_H
 %if %{with java}
 export JAVA_HOME=/usr/lib/jvm/java
-%ifarch %{arm} s390x
+%ifarch %{arm} s390x riscv64
 # getting "java.lang.OutOfMemoryError: Java heap space" during the build
 export JAVA_TOOL_OPTIONS=-Xmx2048m
 %endif
-%ifarch %{arm}
+%ifarch %{arm} riscv64
 # Likely running out of memory during build
 %global _smp_ncpus_max 2
 %endif