WordPress multisite exceeding database connections

Hi,

We are using WordPress 4.3 to run a few thousand websites using multisite feature. We use AWS hosting (Amazon Linux) for the website and AWS RDS server with MySQL on m4.large instance as backend. Last few weeks we are facing issue of database (DB) connections exceeding 256 limit every two-three days. As a result the websites stop working and we have to restart the RDS server to get all the websites running again. The number of users on the primary website is very low. AWS Support has given us some indicators but nothing substantial.

As WP manages all DB connections I have a few questions:
– How can we trace where the DB connections are originating from. What IP etc.
– Can we trace if those connections are being closed. Maybe trace connections as they open and get closed.
– How does WP pool DB connections.
– Can we generate some log of DB connections etc.
– Each of the multisites uses a separate domain than the primary website. How can we know how many users are using all the sites and total statistics for all domains, i.e. total traffic info for all multisite domains. All these sites use the same MySQL server running on RDS.

I searched the internet but didn’t find any discussion on this or similar issue.
Any other suggestions, thoughts and solutions are welcome. We do plan to upgrade to latest WP.

Thanks
Amal

• This topic was modified 3 years, 11 months ago by amsharma.