It may be a small percentage of total power at full load but what about at idle? Modern CPUs try to optimize power usage by remaining idle as much as possible. When idle, power usage is roughly in proportion to die area fraction. Since caches have been getting larger and larger this would represent a larger fraction of total power at idle.

Less power is still better. Also, if we have to solve the SRAM scaling problem with 3D chip stacking, this will be an issue.

It's also even more expensive. As if the upcoming nodes weren't already ridiculous in that respect.

It would be very useful in combination with NVRAM main memory since you no longer have to deal with crash consistency issues arising from your cache being wiped on a reboot.

What's the point of reboot, if not to reset state?

Poorly worded on my part, I simply meant restart after a crash.

> For something like a cache on a CPU (the main use of SRAM), what's the purpose of it being non-volatile? SRAM doesn't need refreshing, and it's a relatively small percentage of total power.

It sounds like it would be chosen for other reasons, and there would no purpose for the non-volitiliy beyond it being a nice-to-have in some weird scenarios.

Sort of like using core as main memory. That was just the main memory technology of its day, it happened to be non-volatile, but that wasn't it's main selling point.