Table of Contents
What Java heap sizes are recommended for optimized ADSS Server performance and how to change these?
Java uses a memory heap system which is continuously managed by the Java garbage collector. Oracle recommends increasing this value for server applications; see Tuning Garbage Collection with the 5.0 Java[tm] Virtual Machine. By default ADSS Server has a heap size of min 256 MB and max 1 GB for Core and Console instances while max 2 GB for Service instance. This setting is sufficient in most cases. On Windows 32 systems you cannot go above 1.5 GB. You can have a larger maximum heap size on 64 bit operating systems. Ascertia recommends the heap size as following for the ADSS Server instances:
|Instance||Default Memory||Recommended Memory|
Impact on System:
Increasing the heap size substantially may also have a performance impact on the system. If you set a large heap size, then garbage collection is slower, but it occurs less frequently meaning the JVM will not free up memory so quickly. If you set your heap size in accordance with your memory needs, full garbage collection is faster, but occurs more frequently.
For Windows OS:
In order to change the default heap size within ADSS Server v4.3 and later releases on Windows, follow these steps:
- Stop the ADSS Core, Console and Service instances from Windows NT Services panel.
- Uninstall ADSS Server by running the uninstall.bat file using Run as administrator from location: [ADSS Server Installation Directory]\setup\.
- Make sure that the ADSS Server services are no longer present in the Windows NT Services panel.
- Go to the location [ADSS Server Installation Directory]\tomcat\bin and edit these files in a text editor one by one:
On the end of last un-commented line before param exit, set the values for minimum and maximum java heap space to whatever you wish for your environment. The default configuration is shown here and you need to modify it accordingly:
- Save the changes and execute these files one by one by right clicking and choosing Run as administrator option:
- Start the ADSS Core, Console and Service instances from Windows NT Services panel in order to take the memory changes into effect.
For UNIX OS:
In order to change the default heap size within ADSS Server v4.7.2 and later releases on UNIX follow these steps:
- Stop the ADSS Core, Console and Service instances from UNIX daemon.
- Go to the location [ADSS Server Installation Directory]/tomcat/bin and edit these files in a text editor one by one:
Search for the parameter CATALINA_OPTS and set the values for minimum and maximum java heap space to whatever you wish for your environment for each file:
- Save the changes.
- Start the ADSS Core, Console and Service instances from UNIX daemon.
- You can verify the heap size with jconsle.