use reasonable multiplier values
diff --git a/tools/run_tests/run_tests.py b/tools/run_tests/run_tests.py
index c3d070a..209925b 100755
--- a/tools/run_tests/run_tests.py
+++ b/tools/run_tests/run_tests.py
@@ -296,23 +296,30 @@
if resolver:
env['GRPC_DNS_RESOLVER'] = resolver
shortname_ext = '' if polling_strategy=='all' else ' GRPC_POLL_STRATEGY=%s' % polling_strategy
- timeout_scaling = 1
-
- if auto_timeout_scaling and polling_strategy == 'poll-cv':
- timeout_scaling *= 5
-
if polling_strategy in target.get('excluded_poll_engines', []):
continue
- # Scale overall test timeout if running under various sanitizers.
- config = self.args.config
- if auto_timeout_scaling and ('asan' in config
- or config == 'msan'
- or config == 'tsan'
- or config == 'ubsan'
- or config == 'helgrind'
- or config == 'memcheck'):
- timeout_scaling *= 20
+ timeout_scaling = 1
+ if auto_timeout_scaling:
+ config = self.args.config
+ if ('asan' in config
+ or config == 'msan'
+ or config == 'tsan'
+ or config == 'ubsan'
+ or config == 'helgrind'
+ or config == 'memcheck'):
+ # Scale overall test timeout if running under various sanitizers.
+ # scaling value is based on historical data analysis
+ timeout_scaling *= 3
+ elif polling_strategy == 'poll-cv':
+ # scale test timeout if running with poll-cv
+ # sanitizer and poll-cv scaling is not cumulative to ensure
+ # reasonable timeout values.
+ # TODO(jtattermusch): based on historical data and 5min default
+ # test timeout poll-cv scaling is currently not useful.
+ # Leaving here so it can be reintroduced if the default test timeout
+ # is decreased in the future.
+ timeout_scaling *= 1
if self.config.build_config in target['exclude_configs']:
continue