Oracle iPlanet Web Proxy Server 4.0.14 Administration Guide

gc extra margin percentVariable

If garbage collection is triggered by a reason other than the partition’s size approaching the maximum allowed size (gc hi margin percent), the garbage collector will use the percentage set by the gc extra margin percent variable to determine the fraction of the cache to remove.

The valid range for gc extra margin percent is 0 to 100 percent. The default value is 30 percent, which removes 30 percent of existing cache files.