In the last few sessions on Kitely, the issue has arisen in which, on only a four region world (Cortile Lighthouse), the viewer 'stutters'... that is to say, while moving the point of view, the scene moves smoothly for a moment, then freezes, then 'jumps' to where it would have been had the movement continued normally. It is particularly noticeable while using a SpaceNavigator with Flycam.
This issue has arisen almost suddenly, just in the last few sessions. There were no changes in any of the relevant software versions: the OS, Firestorm version, and 3DConnexion device driver version. I've seen no notification that the OpenSim version has changed, so it too is assumed to be the same (to the best of my knowledge). The 3DConnexion and Firestorm versions are the latest available. There is no other software running on the computer when this problem occurs.
The problem is only pronounced on a four region world with content (Cortile Lighthouse - about 8500 objects). It is not apparent on a single region, even with with a high level of content (Serenity Island - about 40,000+ objects) . On a region with zero content, the issue also does not occur. The issue occurs regardless of how much time is spent in a world.
Naturally, I tried shutting down the computer, which means that all software was re-initialized. I also emptied the directory and inventory caches in Firestorm, as well as the inventory trash.
Although I first suspected Firestorm or the SpaceNavigator, there is no stutter on a single region without content, and performance is normal while building a simple item on a single region with just a few prims, or moving about on Serenity Island with a very large amount of prims. The four region world only has prims and textures, no mesh, no scripts, no animation. And a final note, the stutter occurs even with graphics on low and building attempted far from the current content. In other words, the viewer is not trying to show a lot of content when the stutter occurs out of range of the render distance of existing content. This makes the source of the stutter unclear, other than the characteristic that there are four regions and some content located somewhere on them.
Here are some system stats:
Firestorm version 18.104.22.168150
Mac OS X 10.11.6
Graphics NVIDIA GTX 780
Software loaded: Safari; Firestorm
Viewer Graphics setting: Low to high (stutter occurs at all graphics settings).
Ping Sim: 18ms
Packet Loss: 0%
Max bandwidth: 500 - 1500 (both levels applied for testing)