speed of tiles generation

Hello
i installed tile server on a vm with 8 core cpu and 8 gig of ram
just have maps of uk
and every thing working good
but its a bit slow
after any zoom i must wait 7-10 seconds to show the tails
is there any way to speed up the tasks?

Generally speaking I’d recommend:

o Use SSD disk
o Prerender tiles up to zoom level 12

I look after https://map.atownsend.org.uk/ and the server behind that is a Hetzner CX41 (see https://www.hetzner.com/cloud ; not in any way afilliated to them, just giving an example of the spec). Everything up to Z12 is “already there”, as you zoom in the time taken to render higher zoom tiles is less than the browser timeout so even when there’s nothing at the correct zoom level to display the library (Leaflet in my case) can show a blown-up lower zoom tile for a few seconds before the new one is available. The user doesn’t get patches of grey.