13.3.9. Scaling

When a cartridge is added to a scalable application, the Min and Max parameters define the scaling limits for that cartridge. If both the Min and Max values are set to 1, this means that the cartridge cannot scale. If the Max value is set to -1, the cartridge can scale up to the user's maximum gear limit. These limits are applicable for both automatic and manual scaling of cartridges.

Note that when using Group-Overrides to collocate two or more scalable cartridges, the scaling limits of both cartridges must match. However, there may be cases where this limitation may not be ideal; for example, a web_proxy category cartridge collocated with a web_framework category cartridge. In such a case, it is not recommended to have the web_proxy cartridge be located on every gear that holds the web_framework cartridge. The Multiplier parameter allows you to place a cartridge only on certain gears within a group instance, rather than all of them. For example, if the Multiplier is set to 3, every third gear within the group instance gets the cartridge installed on it. If it is set to 1, then the cartridge gets installed on all gears within the group instance.