PlayStation 3 Emulator Delivers Modest Speed-Ups with Disabled E-Cores on Intel Alder Lake Processors

According to some testing performed by the team behind RPCS3, a free and open-source emulation software for Sony’s PlayStation 3, Intel’s Alder Lake processors are enjoying a hefty performance boost when E-Cores is disabled. First of all, the Alder Lake processors feature a hybrid configuration with high-performance P-cores and low-power E-cores. The P-cores are based on Golden Cove architecture and can execute AVX-512 instructions with ease. However, the AVX-512 boost is only applicable when E-cores are disabled as software looks at the whole package. Officially, Alder Lake processors don’t support AVX-512, as the processor’s little E-cores cannot execute AVX-512 instruction.

Thanks to the team behind the RPCS3 emulator, we have some information and tests that suggest that turning E-cores off gives a performance boost to the emulation speed and game FPS. With E-Cores disabled, and only P-cores left, the processor can execute AVX-512 and gets a higher ring ratio. This means that latency in the ring bus is presumably lower. The team benchmarked Intel Core i9-12900K, and Core i9-11900K processors clocked at 5.2 GHz for tests. The Alder Lake chip had disabled E-cores. In God of War: Ascension, the Rocket Lake processor produced 68 FPS, while Alder Lake produced 78 FPS, representing around 15% improvement.

This suggests that more applications can take advantage of disabling E-cores, especially if the application has support for AVX-512 instructions, where only P-cores can execute them. So it remains to be seen throughout trial and error if more cases like this appear.