The size of the attribute table can be configured through the SoftDevice API when enabling the BLE stack.
The attribute table size, ATTR_TAB_SIZE, has a default value of 0x580 bytes. Applications that require an attribute table smaller or bigger than the default size can choose to either reduce or increase the attribute table size: the minimum attribute table size is 0xD8 bytes. The amount of RAM reserved by the SoftDevice, and the minimum required start address for the application RAM, APP_RAM_BASE, will then change accordingly.
For more information on how to configure the attribute table size, refer to the S130 SoftDevice API.