I was just about to make a post about grasshopper slowing down even when the solver is disabled when I realised it is caused by the autosave feature.
In an attempt to optimise my solution I internalised some of the data that I was happy with. Unfortunately this means that every time I change anything in the solution it autosaves and has to resave all of the internalised data.
Not sure there is a solution to this other than not internalising large amounts of data (worked out as around 80mb file). I’m now using data dams instead.