diff --git a/userspace/gcov.sh b/userspace/gcov.sh
index 70ad92d14..4a87ccbad 100755
--- a/userspace/gcov.sh
+++ b/userspace/gcov.sh
@@ -60,7 +60,7 @@ find . -name "*.gcda" -exec rm {} +
 find $NVGPU_SRC_ROOT -name "*.gcda" -exec rm {} +
 
 #Run unit tests
-./unit.sh -j 2
+./unit.sh
 OUT=$?
 if [ ! $OUT -eq 0 ]; then
 	echo "ERROR: Unit test run failed."
diff --git a/userspace/unit.sh b/userspace/unit.sh
index 85dcb9dfb..de85b5c91 100755
--- a/userspace/unit.sh
+++ b/userspace/unit.sh
@@ -41,7 +41,8 @@ if [ -f nvgpu_unit ]; then
 else
         # running on host
         LD_LIBRARY_PATH="build:build/units"
-        NVGPU_UNIT=build/nvgpu_unit
+        # On host, must run single-threaded to avoid high VAs
+        NVGPU_UNIT="./build/nvgpu_unit --num-threads 1"
 fi
 export LD_LIBRARY_PATH