Intel Core i9 9900K Spectre Mitigation Benchmarks

The Stress-NG kernel micro-benchmarks with the socket activity measurement sees the Spectre mitigations still needed lowering the performance by about 14%.

The context switching overhead also remains significant with this latest Core i9 9900K processor.

The message passing performance also remains significant but not as bad as we've seen with older CPUs needing KPTI.

Memcached is one of the real-world workloads still sharply affected by the still necessary mitigations.

The NGINX web server performance improved by 13% when running the risky configuration of Retpolines and SSBD mitigations flipped off.

The performance cost is down with at least no longer needing Kernel Page Table Isolation (KPTI) for Meltdown and also the L1TF/Foreshadow patches, but depending upon your workloads, the mitigations for the other Spectre vulnerabilities can still be costly. At least with forthcoming Cascade Lake parts, Intel has in-silicon mitigations coming for Spectre Variant Two (no more Retpolines needed).