gitk: How to tell it “stop, don't load more commits”?

Just gitk or gitk --all can try to fill up all memory on big repository.

I know than I can gitk -n 1000 to limit it. Also I can killall git (or even Alt+SysRq+F if haven't stopped it in time) to stop it in middle of thrashing.

Is there more proper way to make gitk don't load more commits and stop it's git subprocess without hacks or lengthy gitk restart?