> Think of a slider of sensitivity; we're currently closer to the insensitive size, because we're a high-growth business.
If the big-tech layoffs are any indication of a general trend toward belt-tightening, then reducing headroom, and even over-subscribing servers shared-hosting-style, must be tempting.
Even in a case where they for some reason might want to oversubscribe or at least keep the number of servers smaller the scheduling decision they want seems to be different.
It's the difference between "fit this into the smallest number of nodes so that we can shut down some nodes [possibly rented by the hour] if possible" vs "these nodes are sitting there whether or not they're doing anything, so spread the nodes across them".
In the long run there may come a time where packing tighter matters, e.g. if they become big enough to run their own data centres, where shutting down servers dynamically to save power might become worth it, but typical colo contracts for smaller number of racks rarely makes it worth your while to turn servers off.
If the big-tech layoffs are any indication of a general trend toward belt-tightening, then reducing headroom, and even over-subscribing servers shared-hosting-style, must be tempting.