Slow mode?

[scatteredbomb]

My site is experiecing a surge in activity this morning and causing server load to go crazy. I remember there used to be a 'mode' you flip on that would disable features in order to speed up the site (or at least to temporarily reduce server load). Is this still a thing? 

[Marc]

There is no such thing as a 'slow mode' you refer to there, no.