comment on multicore in test runner

1 files changed, 3 insertions, 0 deletions

diff --git a/tests/runner.py b/tests/runner.py
index 17d6ef0c..bbe9715c 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -10,6 +10,9 @@ These tests can be run in parallel using nose, for example
 
 will use 4 processes. To install nose do something like
 |pip install nose| or |sudo apt-get install python-nose|.
+
+Note however that emcc now uses multiple cores when optimizing,
+so you may prefer to use fewer cores here.
 '''
 
 from subprocess import Popen, PIPE, STDOUT