Enabling more renderers makes it slow to start Blender (at least on Windows)

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1

After I click Blender in the Start Menu, there is a moment when Blender’s window is just grey, before the UI appears. I felt that it had gotten worse, so I tried to find the reason by disabling all plug-ins and enabling them one by one. It seems that the renderer plug-ins are the biggest culprits. Notably, the Radeon ProRender, and LuxCore.

But does it have to be like this? Those two renders are not even my default render, and I do not even use them often. So, why does Blender have to initialise them at the beginning? Can’t Blender initialise them in the background after the UI has been initialised, or the first time when the user switches to the renderer?

I have disabled the two renders to make Blender start faster, but it will be cumbersome to open the Preferences and enable them, when I want to use them.

2

Unfortunately, I think this may be a known limitation. All enabled addons are registered by Python code when Blender starts, and whenever Python is running, Blender’s UI has to wait for it to finish. Normally this is fine since most python scripts finish instantly, but if it has to initialize something like a big external renderer, the lag may be noticeable.

3

I’ve got Blender 2.82 with the latest prorender going and it does not seem to add a lot to the render time. Do you have the latest version of prorender?

I’ve not tried LuxCore.