The following subsections explain how the recommended performance tuning values can be set:

Setting maximum open file descriptor limits

Follow the instructions below to set the maximum open file descriptor limits in Linux:

  1. Log in as a root user.
  2. Open the limits.conf file, which is in the /etc/security/ directory.

  3. Add or edit the following two lines in the file.

    * soft nofile 4096
* hard nofile 65535

     

    • An asterisk * has been added at the start of the entry to set the maximum open file descriptor limit for all the users. However, if you wish to set the open file descriptor limit only for a specific user, enter that respective user's username instead of an asterisk.

    • The soft limit defines the minimum number of file handles or open files that the users will have after they log in. 

    • The hard limit defines the maximum number of file handles or open files that the users will have after they log in. 

      If you encounter an error message about running out of file handles, then the hard limit can be increased.

Setting JVM memory allocation limits for Stratos

Follow the instruction below to change the JVM memory allocation limits for Stratos:

  1. Navigate to the <STRATOS_HOME>/bin/ directory and open the stratos.sh file.
  2. Locate the following entry:
    -Xms256m -Xmx1024m -XX:MaxPermSize=256m \ 
  3. Update the above entry as follows based on the Stratos deployment and save the stratos.sh file.
    • For a single JVM deployment
      -Xms256m -Xmx2048m -XX:MaxPermSize=256m \
    • For a distributed deployment (multiple JVM deployment)
      -Xms256m -Xmx4096m -XX:MaxPermSize=256m \

The Java Virtual Machine (JVM) memory allocation pool limits have been described as follows:

    • -Xms -   This specifies the initial memory allocation pool for a JVM.
    • -Xmx -   This specifies the maximum memory allocation pool for a JVM.
    • -XX:MaxPermSize -  The permanent space is where the classes, methods, internalized strings, and similar objects used by the JVM are stored and never deallocated. This defines the maximum space that will be allocated as the permanent space.
  • No labels