why the gpu_ray sensor number in a world is limited ?

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Hello all,

I am trying to accurately simulate a velodyne sensor with 16 plains :
As the needed angular resolution is 0.1deg and the rotation rate is about 10Hz, I attempting to achieve this by creating a plugin that reads data fro 36 rotating, ray sensors, that are tilted on the side.

If i use regular ray sensors, things are working fine. But if i switch to gpu_ray, and use more than 16 gpu_ray sensors some of them do not produce any data, and if i use more than 24 sensors gazebo crashes

I am using : Gazebo 8 (also happens with Gazebo 5 and 7) Ubuntu 16.04 CPU : Xeon(R) E5-1620 v3 @ 3.50GHz × 8 RAM : 16G GPU : Nvidea Gefoce GTX1080 (also happens with Quadro K2200)

If anybody have any idea, please, give me some direction

(as sloretz suggested i have also created a Bittbucket issue)