1.18 has significantly more disk writes into save files (mostly in mca) during walking/running in singleplayer on fresh world with rates up to 2 mb/sec (for example in 1.17 and earlier HDD was dead silent with very little writes), that leads to lots of stuttering and constant (literally) HDD noise in 1.18.

I've checked it in Process Explorer and total writes just for creative flying without boost for 1 minute straight south gave me 200 mb of writing in 1.18 and I had to wait 10-20 seconds just to hear stop of HDD activity. This is not OS swapping, memory was available.

I assume this is less noticable on SSDs since they are faster, have no noise and going mainstream, but excessive writes is bad for SSDs too.

Render distance was 12, mipmaps off, vsync off.