do_cmake: warn users about slow debug builds #25478
Merged
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Spent more time than I want to admit bisecting master over the weekend looking for a 5X random write performance regression on NVMe. Finally I figured out that do_cmake.sh was changed to create debug builds by default in #24133. 😅 This PR adds copious warnings so that I hopefully won't have to bisect this again in six months after I've forgotten that we changed the default behavior.