The animation in question. When the left window slides in is when it stutters throughout the animation, but when it goes the other way (so left window slides out) then it doesn't stutter. Green tint means that part is rendered normally; white means it is scanned out directly onto a plane.

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   Ivan Molodetskikh (yalter@mastodon.online)'s status on Wednesday, 01-Nov-2023 08:47:02 JST Ivan Molodetskikh

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   After adding dmabuf feedbacks to niri, I stumbled upon an extremely strange performance problem when using overlay planes. One specific animation, with a GTK 4 window open, stutters, but only when going into one direction.

   Spent half a day debugging it with Smithay developers. Couldn't crack it yet; for some reason an AMDGPU kernel worker just... takes a while under those specific conditions, causing delayed frames. Seems to be doing the same thing as in the normal case, just... slower somehow.