This section describes the SMS stack disk monitors. The SMS stack stores the messages before segmentation and reassembly.
There must be adequate disk space to receive messages. When there is insufficient memory the SMS reception is suspended except for the Class 0 SMS. The disk monitor notifies the telephony server to resume SMS reception if the disk space is available.
The disk space limits are defined in the SMSU resource file. There are two limits specified in the resource file:
High limit defines the minimum amount of space required to receive Class 0 messages. The default value is 16 kilobytes.
When the disk space is low limit, only Class 0 messages are received. The default value is 8 kilobytes. The low limit is ignored if the device supports Class 0 messages with no disk space. In this case memory is allocated to store the Class 0 messages. The allocated memory is created at the phone boot time.