Lighting calculation is very slow in the Linux environment

V-Ray V-Ray Application SDK Issues
1

We tested stable SDK versions from 6.20 to 7.20 on both CentOS 7 and Ubuntu 24.04.

We found that when starting rendering through the SDK on Linux, the lighting calculation phase takes much longer than when rendering through the standalone application.

The test project was CPP example 02-production-rendering. We used the output resolution defined in the scene settings and disabled VFB. VFB was also disabled when launching rendering from the standalone application.

We captured the thread states and found that a large number of threads were sleeping at that time, which may be one of the reasons for the slowdown. If you have any information, please feel free to contact us. Thank you.
test.rar (424 KB)

2

Additional note: this issue did not occur in SDK 5.2.

3

Can you, please, try the new version 7.3?

4

I tested version 7.3 of the SDK, and the issue still exists. The problem becomes more noticeable when the output resolution reaches 4000.