I recently switched to using czml instead of the primitive API.I posted a sample of the czml I'm using below. I split it up by the parts that I am most interested in at the moment, which are timeseries steps for the extruded height and color.
The czml below is for just one of the extruded ellipses. Ideally, I would like to have about 20,000. However, I can't seem to get more than 100 without the render speed slowing to a crawl.
I am currently approaching this problem from 3 angles:
1) Trying to move more of the rendering to the GPU. At the moment, it seems GPU calculation is turned off, so I'm looking into turning this on to take a load off the CPU.
2) Limiting the data to only show the most interesting data points to cut down on the total size.
3) optimizing the czml such that it can render more efficiently. (this is where I'm hoping you might have some advice)
Or maybe this just isn't something that is possible with Cesium? I suppose that is a possibility as well. But hopefully not