diff --git a/tools/run_tests.py b/tools/run_tests.py
index baff4db61..2eae19e8f 100755
--- a/tools/run_tests.py
+++ b/tools/run_tests.py
@@ -228,6 +228,10 @@ def main(argv):
 	if 'time_limit' in cfg:
 		time_limit = int(cfg['time_limit'])
 
+	# it takes a bit longer to run in valgrind
+	if 'launcher=valgrind' in options:
+		time_limit *= 2
+
 	architecture = platform.machine()
 	build_platform = platform.system() + '-' + platform.release()