CDR_EVALTHREADS Configuration Parameter

Specifies the number of group evaluator threads to create when Enterprise Replication starts, and enables parallelism.

onconfig.std value
1,2
units
evaluator thread instances
range of values
first value: 0 or a positive integer representing the number of evaluator threads to create per CPU VP. Although evaluator threads are not assigned to specific CPU VPs, you can create evaluator threads that are proportional in number to the number of CPU VPs.

second value: 0 or a positive integer representing the additional number of evaluator threads to create irrespective of the number of CPU VPs.

Do not set both CDR_EVALTHREADS values to 0.

takes effect
When the database server is shut down and restarted, or immediately after the cdr change onconfig command is used
Enterprise Replication evaluates the images of a row in parallel to assure high performance. Figure 1 illustrates how Enterprise Replication uses parallel processing to evaluate transactions for replication.
Figure 1. Processing in Parallel for High Performance
begin figure description - This figure is described in the surrounding text - end figure description
The CDR_EVALTHREADS configuration parameter specifies the number of grouper evaluator threads to create when Enterprise Replication starts and enables parallelism. The format is:
(per-cpu-vp,additional)

The following table provides four examples of CDR_EVALTHREADS.

Number of Threads Explanation Example
1,2 1 evaluator thread per CPU VP, plus 2 For a 3 CPU VP server: (3 * 1) + 2 = 5
2 2 evaluator threads per CPU VP For a 3 CPU VP server: (3 * 2) = 6
2,0 2 evaluator threads per CPU VP For a 3 CPU VP server: (3* 2) +0 = 6
0,4 4 evaluator threads for any database server For a 3 CPU VP server: (3 * 0) +4 = 4
Attention: Do not configure the total number of evaluator threads to be smaller than the number of CPU VPs in the system. As noted above, do not set both CDR_EVALTHREADS values to 0.

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