If the Memory Tuning feature is enabled during setup, the setup algorithm determines the maximum JVM heap size based on the total amount of available system memory. If Memory Tuning is not selected, the server allocates a maximum JVM heap of 384 MB. The Directory Server also allows you to specify the maximum heap size during the setup process. You can enable Memory Tuning during the setup process by selecting the feature during the interactive command-line mode, adding the --jvmTuningParameter option using the setup tool in non-interactive command-line mode, or regenerating the java properties file with bin/dsjavaproperties and the --jvmTuningParameter options (seen in JVM Properties for Server and Command-Line Tools page 75).
If Memory Tuning is selected, the server can allocate the maximum JVM heap depending on the total system memory. The following table displays the automatically allocated maximum JVM heap memory based on available system memory.
|Available Memory||Allocated JVM Memory|
|16 GB or more using a 64-bit JVM||The maximum JVM heap size will be set to 70% of total system memory. If the maximum JVM heap size is less than or equal to 128GB of memory (which should be the case for systems with up to 160 GB of memory), then the initial heap size will be set to equal the maximum heap size.|
|6 GB‒16 GB using a 64-bit JVM||total system memory - 4 GB|
|4 GB–6 GB using a 64-bit JVM||2 GB|
|2 GB–4 GB||512 MB|
|1 GB–2 GB||384 MB|