Configuration parameter

 return [
    'user'       => [
        'class'   => ServiceClient::class,
        'host'    => '127.0.0.1',
        'port'    => 18307,
        'setting' => [
            'timeout'         => 0.5,
            'connect_timeout' => 1.0,
            'write_timeout'   => 10.0,
            'read_timeout'    => 0.5,
        ],
        'packet'  => bean('rpcClientPacket')
    ],
    'user.pool'  => [
        'class'  => ServicePool::class,
        'client' => bean('user')
    ],
]; 

As defined above, a user service has the same connection pool configuration parameters as the others.

/docs/2.x/en/rpc-client/setting.html
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