SAP Mobile Server Fails to Start Due to Incorrect JVM Settings

Problem: SAP Mobile Server fails to start because of incorrect or conflicting JVM property settings.

The JVM maximum heap size is set too low and/or a JVM option is missing a space.

Solution: To add a space to a JVM option:

Edit the SMP_HOME\Servers\UnwiredServer\Repository\Instance\com\sybase\sup\server\SUPServer\sup.properties file and search for DJC_JVM_USEROPTIONS.
Add a space before the appropriate option, for example,-Dcom.sap.solutionmanager.url=<SolutionManager_URL>.
Start the SAP Mobile Server by doing one of the following:
- Clicking the Start SAP Mobile Platform Services desktop shortcut.
- Run the start-unwired-server.bat from the command prompt.

Solution: To increase the maximum heap size:

Use updateProps.bat to update the DJC_JVM_MAXHEAP property in the sup.properties file.
Increase the DJC_JVM_MAXHEAP value. The default is 2048MB. Servers with 64-bit operating systems can be set much higher, depending on the available RAM. Example:
```
updateProps.bat -nv "DJC_JVM_MAXHEAP=2048M"
```
Note: For servers with 32-bit operating systems, the MAXHEAP value is limited to 768MB. Some machines will have a maximum that is less than that, for example, 512MB. If the MAXHEAP is set too high, errors are reported in the SMP_HOME\Servers\UnwiredServer\logs\mlsrv_err.log file.
Start the SAP Mobile Server by doing one of the following:
- Click the Start SAP Mobile Platform Services desktop shortcut.
- Run start-unwired-server.bat from the command prompt

Setting SAP JVM options -XX:+UseParallelGC or -XX:+UseParallelOldGC may prevent SAP Mobile Server from starting

While the SAP JVM options -XX:+UseParallelGC and -XX:+UseParallelOldGC can improve server performance, they may conflict with other JVM options set in the previous installation which can prevent SAP Mobile Server from starting.

Solution: If adding these JVM options prevents SAP Mobile Server from starting, run SMP_HOME\Servers\UnwiredServer\bin\restore-workingconfig.bat to restore the options to a working state.