SQLSTATE[HY000] [1040] Too many connections errors

[houseofdeadleg]

I've noticed I'm getting a lot of these errors logged – Error: Exception: SQLSTATE[HY000] [1040] Too many connections (in …/wire/core/ProcessWire.php line 186). Can anyone suggest why this might be the case? Is it likely to be something in the Processwire setup/modules, or more likely to be something from the server/hosting side?

[BitPoet]

It's hard to say definitely, but most times this is an issue that occurs on shared hosting. MySQL has a limit on how many concurrent connections it serves (151 by default, though usually set higher for shared db servers). If this number is reached, new connection attempts return with the error you quoted. If you're on shared hosting, check with your hoster if other users are eating up connections. If you're on a dedicated server, also look if there are other tasks/programs connecting to MySQL at the same time (for example backup/maintenance scripts or database logging facilities). If you haven't made large tweaks to your PW installation or webserver/PHP configuration, the first two are the most likely suspects.