Man, it’d be great if there was some feature that would improve performance with VSM…
" Multiple Lights Performance
Performance in scenes with many small local lights is still a work in progress. For the time being, the best strategy is to enable one pass projection and be very careful with invalidations to keep as many of the pages cached as possible. Multiple local lights will perform far better with Nanite geometry than non-Nanite geometry, so aggressively culling or disabling shadow casting on non-Nanite geometry in the distance can help a lot."