Configuring Unwired Server Performance Properties

To optimize Unwired Platform performance, configure the thread stack size, maximum and minimum heap sizes, user options, and inbound and outbound messaging queue counts.

  1. In the left navigation pane, expand the Servers folder and select a server.
  2. Select Server Configuration.
  3. In the right administration pane, select the General tab.
  4. From the menu bar, select Performance Configuration.
  5. Configure these properties, as required:
    • Host Name – the name of the machine where Unwired Server is running (read only).
    • Thread Stack Size – the JVM -Xss option.
    • Minimum Heap Size – the minimum size of the JVM memory allocation pool, in megabytes. Sybase recommends that this value not fall 500 megabytes for a 32-bit operating system, but 1 gigabyte is recommended. For a 64-bit operating system, Sybase recommends 1 gigabyte for a normal configuration, but 2 gigabyte for a stress configuration (which can vary depending on what RAM is available).
    • Maximum Heap Size – the maximum size of the JVM memory allocation pool, in megabytes. For a 32-bit operating system, Sybase recommends a 1.5 gigabyte maximum heap size value. For a 64-bit operating system, Sybase recommends 1 gigabyte for a normal configuration, but 4 gigabyte for a stress configuration (which can vary depending on what RAM is available).
    Note: The synchronization differencing algorithms are a key feature of replication; this technology runs in the JVM. You must provide adequate memory to these components. If these algorithms are memory starved, the JVM spends an inordinate amount of time garbage collecting memory, and synchronizations back up in the internal queues. You can monitor process memory usage with tools like SysInternal’s Process Explorer to determine the actual amount of memory in use by Unwired Platform, and adjust the JVM heap size accordingly
    Note: Always leave 4 gigabytes for the running of the OS and other applications that may exist on the server.
  6. (Optional) Expand the Show optional properties section and configure these properties, as required:
    • Maximum Number of In Memory Messages – specify the number of in-memory messages to allow.
    • User Options – other JVM options. For example, you can enable JVM garbage collection logging by setting -XX:+PrintGCDetails. Or you can set the permanent space which allocated outside of the Java heap with DJC_JVM_MAXPERM, for example, DJC_JVM_MaxPerm = 512.
    • Inbound Messaging Queue Count – the number of message queues used for incoming messages from the messaging-based synchronization application to the server. Sybase recommends a choose a value that represents at least 10% of active devices.
    • Outbound Messaging Queue Count – the number of message queues used for outbound messages from the server to the messaging-based synchronization application. Sybase recommends a choose a value that represents at least 50% of active devices. However, if you are running 32-bit operating system, do not exceed a value of 100% of active devices.
    • Subscribe Bulk Load Thread Pool Size – the maximum number of threads allocated to initial bulk load subscription operations. The default value is five. Setting the thread pool size too high can impact performance.
    Note: If you increase either queue count property, ensure you also increase the MaxThread property in the <hostname>_iiop1.properties file.
  7. Click Save.
Parent topic: Server Properties
Related concepts
General Server
Related tasks
Saving and Refreshing an Unwired Server Configuration
Reviewing Pending Changes
Viewing Unwired Server Properties