Understanding the CDC Replication memory footprint

Current versions of CDC Replication on Linux®, UNIX, and Windows platforms are written in the Java™ programming language. The memory specified in the CDC Replication configuration tool refers to the amount of memory that the Java Virtual Machine (JVM) will allocate to CDC Replication to run. This memory is strictly enforced by the JVM itself and the JVM will ensure that it is not exceeded.

The amount of memory overhead consumed by the JVM itself can also change over time. This is especially true for Linux and UNIX systems. For those systems, once the operating system allocates memory to a process, it is not reclaimed until the process ends. Thus, the total amount of memory for any given process never goes down.

Given these factors, you should expect that more memory is used by CDC Replication than is allocated in the configuration tool. CDC Replication has no control over this memory usage and cannot track or otherwise manage it.