Major problem in method:
io.agroal.pool.ConnectionPool#idleValidation
if we have idle connection (ConnectionHandler#isIdle return true) then in method 'ConnectionPool#performValidation' if connection is valid (ConnectionHandler#isValid return true) then handler marked with 'CHECKED_OUT' status
and method ConnectionPool#idleValidation return false
which is invalid because after it inside method:
ConnectionPool#getConnection this connection will be skipped
while ( idleValidationEnabled && !idleValidation( checkedOutHandler ) )
so it remains stuck with 'CHECKED_OUT' status and will be returned to the pool only after manual flush
I think it looks like there are missing return statement in ConnectionPool#idleValidation method and correct method should look like this:
private boolean idleValidation(ConnectionHandler handler) { if ( !handler.isIdle( configuration.idleValidationTimeout() ) ) { return true; } if ( handler.setState( CHECKED_OUT, VALIDATION ) ) { return performValidation( handler, CHECKED_OUT ); } return false; }
and it actually worked correctly before refactoring, see this method in 1.12 version:
private boolean idleValidation(ConnectionHandler handler) { if ( !handler.isIdle( configuration.idleValidationTimeout() ) ) { return true; } fireBeforeConnectionValidation( listeners, handler ); if ( handler.setState( CHECKED_OUT, VALIDATION ) ) { if ( configuration.connectionValidator().isValid( handler.getConnection() ) ) { handler.setState( CHECKED_OUT ); fireOnConnectionValid( listeners, handler ); return true; } else { handler.setState( FLUSH ); allConnections.remove( handler ); metricsRepository.afterConnectionInvalid(); fireOnConnectionInvalid( listeners, handler ); housekeepingExecutor.execute( new DestroyConnectionTask( handler ) ); } } return false; }
so in 1.12 version method ConnectionPool#idleValidation return true for valid connections. Please fix it in new release.
