diff --git a/cmake/ci.cmake b/cmake/ci.cmake
index 8794ed078..f5ac2962c 100644
--- a/cmake/ci.cmake
+++ b/cmake/ci.cmake
@@ -1,5 +1,5 @@
 # number of parallel jobs for CTest
-set(N 10)
+set(N 4)
 
 ###############################################################################
 # Needed tools.