TDP Options - Teradata Director Program

Teradata Director Program Reference

Product
Teradata Director Program
Release Number
15.00
Language
English (United States)
Last Update
2018-09-28
dita:id
B035-2416
lifecycle
previous
Product Category
Teradata Tools and Utilities

TDP Options

To provide for memory acquisition during system operation without incurring the high overhead associated with the GETMAIN/FREEMAIN memory services, TDP acquires units of main memory, or cells, from its own, more efficient memory manager.

During startup, the memory manager pre-allocates a number of cells in sizes that are convenient for use by TDP. The sizes of the cells are internal constants. The initial number of cells is an internal default.

 

WHEN a . . .

THEN the . . .

TDP subtask requests a cell from the memory manager, but all available cells are being used by other TDP subtasks

memory manager does one of the following:

  • Obtains a single cell using a GETMAIN call to the operating system
  • Places the requesting subtask into a wait for memory
  • requester is placed into a wait

    wait ends when another TDP subtask releases a cell.

    The decision to use GETMAIN or wait is based on the cell size and the identity of the requesting subtask.