This feature request belongs to a bundle of two, which I decided to fill separately. The goal of the request is to offer a way to detect and react to the events when the region or parcel reaches the prim limits, before it happens and the region starts returning objects, because this destroys the scenery and can lead to frustration by the owners. The other feature request is linked below.
The idea consists off two parts. Part 1 is whenever the viewer is taking an object into the inventory, the inventory asset stores additionally the last value of the land impact of the object. This way when the region tries to rez it, it can detect beforehand if the object would overfill the parcel. In the case this information is not available, the region will do it traditional way.
The part 2 is to run the region in two modes, parallel and sequential mode. And maintain a threshold value, which can be changed region-wide.
When the land impact on the region did not reach the threshold value, the risk of overfilling the region is low and the region works in parallel mode, then the rez events occur concurrently and can happen independently.
When the region usage reaches the object threshold, the region runs in sequential mode and all rez operations run sequentially, whenever a script tries to rez an object, and the region is performing rez operation for an other object or resident, all scripts in the object in question stop until the region is finished with other rezzing processes.
This way the region can stop rezzing before overfilling and returning prims.