Freezed Props drop Server-FPS

Hey
i have a problem with my Linux Garrysmod Server.

if i have 20 Freezed Props (Every prop is Welded to each other- like smart weld tool)
if i touch these props with an oder unfreezed prop, my server fps drop down under 10
this problem will not appear when i unfreeze all props, after freezing it comes again

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