MySQL Too many connections error
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*Except Fisheye and Crucible
Summary
Confluence server runs into issues due to the following errors in atlassian-confluence.logs
WARN [C3P0PooledConnectionPoolManager[identityToken->2rxoowa718mgiwy1hbhgv1|373cc023]-HelperThread-#0] [mchange.v2.resourcepool.BasicResourcePool] log com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@769977cc -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
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Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Too many connectionsEnvironment
Confluence configured with MySQL database
Cause
This happens because MySQL database has maxed out its connection limit and can't accept any more connections from clients.
Solution
To avoid this issue, increase the maximum connection limit in MySQL server's configuration. Usually this is specified with the max_connections parameter in MySQL server configuration. A restart of MySQL will be required for these changes to take affect.