3 ms·

I kind of did answer a different question, but you sort of affirmed my answer & proved my point. If the "expected range" of your CPU utilization is only 25%, th

I kind of did answer a different question, but you sort of affirmed my answer & proved my point. If the "expected range" of your CPU utilization is only 25%, then you are knowingly paying for 3x more CPU than you are actually every planning to use. I suppose if you got that cash money and are willing to burn it, nothing I can say will stop you. I just question the logic of it. As for why they suddenly dropped? I'll leave that to someone who knows this particular system far better than I do.

sradman 6y ago
I think Jeffbee resolved my confusion; InnoDB uses spin locks that chew up cpu cycles when the request rate exceeds the I/O rate. This is not as bad as it sounds; it uses extra power and generates extra heat but it is not doing any extra real work. InnoDB cores run at either 25% or 90% but the 90% indicates that you need an I/O upgrade not more CPU cycles. Optimizing for CPU efficiency in a system that is I/O bound will not save significant money. Memory and NVMe are the critical factors and with the master/slave replication used, network I/O significantly undercuts the peak performance this single server is capable of.