I am using the latest version of Piwik. My Piwik server has been running fine for about one year (database about 500 MB ) but in the last week I have got this error message about four times.
Cannot connect to the database:
SQLSTATE[HY000]  Can’t connect to MySQL server on ‘127.0.0.1’ (111)
This may be a temporary issue, try refreshing the page. If the problem persists please contact your Piwik administrator.
After I restart MySQL the server is ok again but then after a while it stops again.
Any ideas please?