> The power savings delivered by the smaller process geometry have allowed us to replace Cortex-A53 with the much more powerful, out-of-order, Cortex-A72 core; this can execute more instructions per clock, yielding performance increases over Raspberry Pi 3B+ of between two and four times, depending on the benchmark.

Looks like the Pi 4 will be vulnerable to Spectre. That's unfortunate, since it seems like this is quite an upgrade otherwise.

https://en.wikipedia.org/wiki/Spectre_(security_vulnerabilit...

> ARM has reported that the majority of their processors are not vulnerable, and published a list of the specific processors that are affected by the Spectre vulnerability: Cortex-R7, Cortex-R8, Cortex-A8, Cortex-A9, Cortex-A15, Cortex-A17, Cortex-A57, Cortex-A72, Cortex-A73 and ARM Cortex-A75 cores.