memcache.go
func (c *Client) Close() error {
	c.mu.Lock()
	defer c.mu.Unlock()
	c.closeIdleConns()
	c.freeconn = nil
	c.maxIdlePerAddr = 0
	return nil
}
func (c *Client) Close() error {
	c.mu.Lock()
	defer c.mu.Unlock()
	c.closeIdleConns()
	c.freeconn = nil
	c.maxIdlePerAddr = 0
	return nil
}
// Close closes all currently open connections.