rsdb/tbi_buffer_area_MB is a SAP Parameter attribute which is used to control Size of the table buffer in MB information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
This parameter defines the size of the table buffer in MB.
The size includes all kinds of buffered tables (fully buffered,
generic buffered and single row buffered).
It replaces the profile parameters rttb/buffer_length and
zcsa/table_buffer_area.
If rsdb/tbi_buffer_area_MB is not set or the default value is not
changed,
but rttb/buffer_length and zsca/table_buffer_area are set, for backwards
compatibility,
the size of the table buffer is automatically calculated by the
following rule:
buffer size (byte) = ((rttb/buffer_length * 1024) +
(zsca_table_buffer_area * 1024 * 1024 ) ) * 1.1
See SAP Parameter Documentation for full SAP documentation for this profile parameter.