Thread:Manual talk:Pywikibot/ERROR: "CRITICAL: Waiting for 1 network thread(s) to finish."

I changed wiki server and updated mediawiki 1.25.1 from 1.24.2 recently.

But, when I use replace.py, It displays error that "CRITICAL: Waiting for 1 network thread(s) to finish".

It is no error to login.

Could It caused by HHVM? I also replaced PHP 5.4 with HHVM 3.7.1 when I changed wiki server.

Well, maybe this is not cause. I tested copy of wiki only connected MariaDB in PHP 5.4 on another pysical server, But the error still displayed.