on the 1.17 version when the rain starts in single player I get a harsh lag spike. when I have it on a server it doesn't stop lagging until the rain stops.

Same thing for me. Rain = Lag

Did you try installing sodium? (in 1.17.1)

Me, no. I don't use Sodium. If @ravensniper72 has Sodium, then he should.

Close because outdated.

Client lag or server lag?