Logical Log Configuration Guidelines
Logical logs must be configured correctly for Enterprise Replication.
Use the following guidelines when configuring your logical log
files:
- Make sure that all logical log files are approximately the same size.
- Make the size of the logical log files large enough so that the database server switches log files no more than once every 15 minutes during normal processing.
- Plan to have sufficient logical-log space to hold at least four times the maximum transaction size.
- Set LTXEHWM (long-transaction, exclusive-access, high-watermark) 30 percent larger than LTXHWM (long-transaction high-watermark).
Important: If you specify that the database server
allocate logical log files dynamically (DYNAMIC_LOGS), it is recommended
that you set LTXEHWM to no higher than 70 when using Enterprise Replication.
For more information about logical logs and these configuration parameters, see Informix® Administrator's Reference and Informix® Administrator's Guide.
The database server can add logs dynamically when Enterprise Replication approaches a potential log wrap situation if the CDR_MAX_DYNAMIC_LOGS configuration parameter is set to a non-zero integer.