DS - Define Size of Storage Buffer

This Natural profile parameter defines the default initial size of various Natural storage buffers. It corresponds to the NTDS macro in the Natural parameter module.

Possible settings See DS Parameter Syntax.
Default setting See Table of Buffer Sizes.  
Dynamic specification yes This parameter can only be specified dynamically. In the Natural parameter module, the corresponding macro NTDS is used instead.
Specification within session no  


  1. In previous versions of Natural, individual profile parameters (for example, SSIZE) were used to define the sizes of the buffers. The DS profile parameter is a universal parameter to specify all buffer sizes.
  2. You may continue using the individual parameters or you may use the individual parameters in parallel to the parameter DS. During the dynamic parameter evaluation, individual buffer size parameters are converted internally into the new DS parameter format, for example, SSIZE=55 is converted into DS=(SSIZE,55).
  3. However, there are some buffer sizes (for example, ESIZE, VSIZE, etc.) which cannot be specified by the profile parameter DS, due to certain reasons, for example, the size is part of a larger buffer or the size defines the total maximum of a number of buffers.
  4. For further information, see Natural Storage Management and General Rules for Parameter Usage in the Operations documentation.

The following topics are covered below:

DS Parameter Syntax

The DS parameter is specified as follows:



Syntax Element Value Explanation
name 1 - 8 characters. The buffer name (1-8 characters), see Table of Buffer Sizes.
size - The buffer size in kilobytes. For limit values, see Table of Buffer Sizes.

Multiple pairs of buffer name and size values can be specified; see Example of DS Parameter.

NTDS Macro Syntax

The NTDS macro is specified as follows:

         NTDS  name,size
         NTDS  name,size


Syntax Element Value Explanation
name 1 - 8 characters. The buffer name (1-8 characters), see Table of Buffer Sizes.
size - The buffer size in kilobytes. For limit values, see Table of Buffer Sizes.

A separate NTDS macro must be specified for each pair of name and size values; see Examples of NTDS Macros.

Table of Buffer Sizes

Buffer Name Description Buffer Size (KB) Default Available as subparameter of DS and alternatively as individual profile parameter
ASIZE Entire System Server auxiliary buffer 0 or 64 - 512 0 yes

For details, see description of profile parameter ASIZE.

BSIZE Size of EntireX Broker buffer 0 or 1 - 64 0 yes
CSIZE Size of Con-nect/Con-form buffer area 0 or 1 - 512 0 yes
DATSIZE Size of buffer for local data 10 - 2097151 32 yes
DSIZE Initial size of DBLOG buffer 0 or 2 - 2097151 2 yes

The individual profile parameter DSIZE allows you to set a maximum size in addition.

EDPSIZE Size of the Software AG Editor auxiliary buffer pool 0 or 48 - 2097151 0 yes
EXCSIZE Size of buffer for Natural Expert C interface n/a n/a yes

This subparameter is only retained for compatibility reasons.

EXRSIZE Size of buffer for Natural Expert rule tables n/a n/a yes

This subparameter is only retained for compatibility reasons.

FLTUSER Size of buffer for fast locate table and subroutine cache.

Information contained in the fast locate table improves performance when Natural objects are called repeatedly. Information contained in the subroutine cache improves performance when the name of the module in which the subroutine is defined is being retrieved from the subroutine name specified with the PERFORM statement.

The FLTUSER buffer contains only information related to Natural objects belonging to the user's application.

0 or 4 - 2097151 8 Available only as subparameter of DS.

The value 0 enforces that neither a fast locate table nor a subroutine cache is allocated and will cause more database calls to be issued in order to retrieve information about Natural objects that are to be called. Therefore, the value 0 should only be used in environments where Natural objects of the same name exist in different steplib libraries (see Steplib Libraries in Using Natural), and the steplib libraries should always be searched for an object in the defined order.

The following formula helps estimate the initial buffer size required to store all entries in the fast locate table:

6 KB + (number of objects * 112 bytes)

which corresponds to a setting of DS=(FLTUSER,21).

This specifies the buffer size for the session start; more space is allocated automatically during the session if required.

MONSIZE Size of SYSTP monitor buffer 0 or 5 - 256 0 yes
MULFETCH Size of multi-fetch buffer 0 or 1 - 1024 64 Available only as subparameter of DS.

A value specified for this buffer does not represent the default initial size but the maximum size which can be allocated for multi-fetch purposes.

See Size of the Multi-Fetch Buffer in the Programming Guide.

NAFSIZE Size of buffer for Natural Advanced Facilities 0 or 1 - 64 0 yes
NSFSIZE Size of SAF interface buffer. 0 or 8 - 64 0 Available only as subparameter of DS.

See information on how to adjust the Natural parameter module in Installing and Activating Natural SAF Security in the Natural SAF Security documentation.

RDCSIZE Size of buffer for the Natural Data Collector 0 or 2 - 128 0 yes
RJESIZE Initial size of NATRJE buffer 0 or 1 - 2097151 8 yes
RUNSIZE Size of runtime buffer 10 - 64 16 yes
SSIZE Size of Software AG Editor buffer 0 or 40 - 512 64 yes
TSIZE Size of the buffer for Adabas Text Retrieval 0 or 1 - 2097151 0 yes
WSISIZE Buffer for Natural Workstation Interface 0 or 10 - 256 0 yes
ZSIZE Size of Entire DB buffer area 0 or 1 - 64 0 yes

For detailed information, refer to the descriptions of the individual buffer size parameters.

Example of DS Parameter


Example of NTDS Macro

         NTDS ASIZE,33 
         NTDS TSIZE,60 
         NTDS EDPSIZE,500