piwik/piwik — pull request #6237 by hdi-kw (2014-09-17 15:02:03+00:00)
Title: use php_uname() instead of shell_exec('uname')

This solution works on a host where otherwise I had problems when the archive job was started through cron. Can someone test this on synology if it also works there?
http://php.net/manual/en/function.php-uname.php