TeamCity is a JVM application, and its memory usage can be tweaked like any other JVM application. For large production uses, the defaults may not work, and hence a few tweaks in the heap and PermGen memory allocated to TeamCity may be needed.

Much of the tweaking can be done by passing the appropriate flags, -Xmx (heap space) and -XX:MaxPermSize (PermGen space), to the JVM.

There is no one size fits all solutions here. The exact values to be used will vary from installation to installation based on usage, number of build configurations and projects, and so on. It is recommended that you use a minimum of 750m for the heap space (-Xmx750m) and 270m for the PermGen space (-XX:MaxPermSize=270m) and then raise it from there as needed.

These flags can be passed to the JVM used to run the server using the TEAMCITY_SERVER_MEM_OPTS environment variable.