如何解决致命错误:非超级用户超出连接限制

Question

我已经编写了一个用于批量插入的java代码.我正在使用copy命令为不同的表导入和创建不同的连接对象,但在执行时,程序会抛出以下错误:

FATAL: connection limit exceeded for non-superusers

Answer 1

您已超过PostgreSQL服务器的连接限制.超级用户有一些保留的连接.

要增加连接限制,您必须更改postgresql.conf(默认值为100),它位于PostgreSQL数据目录中.

cat postgresql.conf | grep max_connection max_connections = 100
        # (change requires restart)
# Note:  Increasing max_connections costs ~400 bytes of shared memory per
# max_locks_per_transaction * (max_connections + max_prepared_transactions)

增加限制并重新启动PostgreSQL实例.

警告:增加连接限制将影响内存.

尝试使用应用程序或数据库层中的连接池优化连接.在PostgreSQL上你可以使用Pgpool2.

Answer 2

Are you using a connection pool? Check if connections are closed properly in your code. This should be done in a try-finally block:

Connection connection = dataSource.getConnection();
try {
    ....
}
finally {
    connection.close();
}

If you really need a large amount of connections, set the max_connections-property in postres accordingly.

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