Totally agree on that front. Efficient software = fewer servers. You can't know when to invest in new capacity if you can't tell the difference between hittin

Totally agree on that front. Efficient software = fewer servers. You can't know when to invest in new capacity if you can't tell the difference between hitting the limit of the hardware, and a fixable performance problem. Seemded like Twitter wasn't sure what was going on there for a few years :) We do a lot of finding ENORMOUS performance problems with customer servers - simple stuff like a thundering herd, a vital missing index or a filesystem that's being overtaxed That's the kind of scale we work at. But those sorts of insights can make the difference between "help we might need a new server" and "oh thank god it's all working again".