You can control resident set size (RSS) usage of a zone by setting the capped-memory resource when you configure the zone. For more information, see Solaris 10 8/07: Physical Memory Control and the capped-memory Resource. You can run rcapd in a zone, including the global zone, to enforce memory caps on projects in that zone.
You can set a temporary cap for the maximum amount of memory that can be consumed by a specified zone, until the next reboot. See How to Specify a Temporary Resource Cap for a Zone.
If you are using rcapd in a zone to regulate physical memory consumption by processes running in projects that have resource caps defined, you must configure the daemon in that zone.
When choosing memory caps for applications in different zones, you generally do not have to consider that the applications reside in different zones. The exception is per-zone services. Per-zone services consume memory. This memory consumption must be considered when determining the amount of physical memory for a system, as well as memory caps.
You cannot run rcapd in an lx branded zone. However, you can use the daemon from the global zone to cap memory in the branded zone.