Benchmarking The Performance Impact To AMD Inception Mitigations
For the DaCapo OpenJDK Java benchmarks there was a performance impact namely where using the alternative IBPB mode.
The safe RET mitigation did impact the 7-Zip compression benchmark performance.
One of the real-world areas where the AMD Inception mitigations did hurt the performance was in code compilation speed. The EPYC 7763 server was showing various open-source projects taking a few seconds longer to build now with the safe RET mitigations. Interestingly the new CPU microcode didn't provide much of a difference over the pure kernel-only mitigation run. The alternative IBPB mitigation showed the worst performance penalties.