Think that financial markets activity is usually active in a large segment. A phenomenon may drive people from a region, stressing that region’s allocated rack. Etc. One does now simply advise to size down.

Obviously, if you are consistently throttling expensive silicon to save on (relatively) cheap colo power you are doing it wrong; but it’s not uncommon for there to be a worst-case configuration that exceeds the power draw of an expected workload(like the furmark case that the GPU companies kept whining about being a ‘power virus’ rather than an actual benchmark back in the day); and if you are trying to cut the margins nice and tight it would be reassuring to be able to instruct systems to simply refuse such cases.

On the other hand, that seems like it could turn into a real down-the-rabbit-hole if you’ve got a fairly heterogeneous collection of gear(it’s certainly much less exciting; both as hardware or in terms of power density than it used to be; but something like an HDD shelf deciding to do a full spin up is still a nontrivial swing in power usage and power usage that no one server’s BMC is necessarily going to be aware of); with systems needing to be aware of other systems’ power draws in order to determine what is safe at any given moment.