On this page:

This page provides instructions for changing the Java heap space (Xmx) for both Cassandra and Teamwork Cloud on Linux and Windows, respectively.

Configuring Java heap space for Cassandra

On Linux

To configure Java heap space for Cassandra on Linux, you must set the variables MAX_HEAP_SIZE and HEAP_NEWSIZE which are commented by default in the file cassandra-env.sh. The location of the file cassandra-env.sh depends on the type of Cassandra installation.

  • Package installation: /etc/cassandra/conf/cassandra-env.sh
  • Tarball installation: <Cassandra install folder>/conf/cassandra-env.sh

Uncomment MAX_HEAP_SIZE, HEAP_NEWSIZE variables and adjust MAX_HEAP_SIZE manually. Otherwise, Cassandra will calculate the heap size based on the system's memory using the following formula:

Calculating Java heap size
max(min (1/2 ram), 1024MB), min(1/4 ram, 8GB))

The formula details are outlined below:

  • For the system memory 0-2 GB: use half of it.
  • For the system memory 2-4 GB: use 1 GB.
  • For the system memory 4-32 GB: use a quarter of it.
  • For the system memory more than 32 GB: use 8 GB.

Configuring Java heap space for Teamwork Cloud

On Linux

  • If you start Teamwork Cloud from the executable file twcloud, you can configure the -Xmx parameter from the file jvm.options (located in the same folder).

On Windows

  • If you start Teamwork Cloud from the executable file twcloud.exe, you can configure the -Xmx parameter from the file jvm.options (located in the same folder).
  • If you start Teamwork Cloud from a Windows service, you must use the Registry Editor to update the value.


To change the value using the Registry Editor

1. Run regedit from the command line.
2. Browse for the key HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Apache Software Foundation\Procrun 2.0\Teamwork Cloud\Parameters\Java.
3. Right-click JvmMx and select Modify....
4. Select Base to Decimal and change the value. The value is in megabytes (mb).

Configuring Java heap space for WebApp

Heap space for WebApp is handled by Tomcat.

On Linux

  • Heap settings are located in /opt/local/TeamworkCloud/WebAppPlatform/bin/setenv.sh
    JVM_OPTS="-server  -XX:+UseParallelGC  -Xms4096M -Xmx8192M"

On Windows

  • The heap setting for WebApp is located in the registry


To change the value using the Registry Editor

1. Run regedit from the command line.
2. Browse for the key HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Apache Software Foundation\Procrun 2.0\WebApp\Parameters\Java.
3. Right-click JvmMx and select Modify....
4. Select Base to Decimal and change the value. The value is in megabytes (mb).