A significant source of delay in a structured service is the amount of
time it takes to collect enough data to fill a cell. This period of time
can be reduced by sending cells that are only partially filled with
data (idlePattern octets are added to the ATM payload beyond the
partial fill level).
This attribute specifies the number of payload octets to fill with
data. It is applicable to structured services only, and must be set to
47 for unstructured services.
On a given AAL1 Function Processor, the maximum cell rate that
can be sustained is dependent upon the combined bandwidths of the
provisioned services, and (for structured services) the levels of
partialFill. The smaller the partialFill level, the greater the cell rate
and hence the fewer the services that can be sustained at that fill
level.