To optimize Unwired Platform performance, configure the thread stack size, maximum and minimum heap sizes, user options, and inbound and outbound messaging queue counts.
- In the left navigation pane, expand the Servers folder and select a server.
 
- Select Server Configuration.
 
- In the right administration pane, select the General tab.
 
- From the menu bar, select Performance Configuration.
 
- Configure these replication payload 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. For production recommendations on this value, see Unwired Server Replication Tuning Reference in System Administration.
 
- Maximum Heap Size – the maximum size of the JVM memory allocation pool, in megabytes. For production recommendations on this value, see Unwired Server Replication Tuning Reference in System Administration.
 
- User Options (in Show optional properties) – 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; the maximum perm size must be followed by K, M, or G, for example, -XX:MaxPermSize=512M.  Note that DJC_JVM_MAXPERM is not visible to Sybase Control Center.
 
 
 
- For messaging payloads, click the Messaging tab and configure these properties, as required:
- Maximum Number of In Memory Messages – specify the number of in-memory messages to allow.
 
- 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.
  
- Click Save.