18.4.14 RRNA and RRNB Parameters - Performance Tuning


The number of RRN (Relative Record Number) assignments that are to be pre-allocated when inserting data into a table. The default value is 1, but any value in the range 1 to 5000 is valid.

Using a value such as 100 can substantially improve the performance of an application doing a large numbers of insert operations because 100 RRN numbers are (pre)allocated by a single access to the RRN assignment file, thus minimizing the number of times that the RRN assignment file needs to be accessed.

Using a value other than 1 may of course waste RRN values that are never assigned to an insert operation, thus leading to a faster rate of RRN value consumption than normal.  


Specifies whether Windows operating system file buffering is to be used when accessing the RRN or *AUTONUM data area assignment files. Specify this argument as Y or N. The default is N.

Using Y will increase application performance but it increases the risk that the RRN or *AUTONUM data area assignment file contents may not be flushed to disk in the advent of a catastrophic system failure (eg: power failure) meaning that the contents may need to be correctly reset.

Also see

18.4.4 DBSS Parameter - Performance Tuning