diff --git a/.gitlab-ci/run-test.sh b/.gitlab-ci/run-test.sh
index 853e5132c..c8fe8016f 100755
--- a/.gitlab-ci/run-test.sh
+++ b/.gitlab-ci/run-test.sh
@@ -3,6 +3,7 @@
 set -ex
 
 export PAGER=cat
+export OMP_NUM_THREADS=1
 
 IS_FEDORA=0
 IS_CENTOS=0