Benchmarking AMD FX vs. Intel Sandy/Ivy Bridge CPUs Following Spectre, Meltdown, L1TF, Zombieload

When running some web browser tests in Firefox, the Intel CPUs saw a measurable but small performance hit while the AMD FX CPUs were less touched by their Spectre mitigations. In the case of the Core i7 2700K, the default mitigations led to roughly a 12% drop in the Basemark web browser performance within Firefox while the i7-3770K was just about 4%. (Yes, keep in mind there was a browser version difference due to pesky auto-updating browser, albeit we're mostly looking at Firefox 66.0.5 performance.)

Jetstream 2 also saw a hit to the performance from these CPU mitigations.

It takes longer to create files with the OSBench micro-benchmark as a result of these mitigations.

Thread creation performance is also slower on the Intel CPUs with these mitigations but still came out ahead of the AMD processors tested.

The time to launch programs took a large hit to the performance on the Intel CPUs and especially so when disabling Hyper Threading.

But for the most part, the Intel Sandybridge/Ivybridge performance was still better than the AMD FX-8300 series processors benchmarked.

Lastly is a look at the geometric mean for all of the tests carried out successfully on all of the processors/combinations. The Intel Sandybridge/Ivybridge CPUs all basically remained faster than the AMD FX CPUs benchmarked even when mitigated and disabling SMT with the exception of the Core i3 2120. The Core i3 Sandybridge processor's geometric mean went from being ahead of all the FX processors to around the speed of the FX-8320E with the default mitigations and behind if disabling Hyper Threading. The Intel Core i5/i7 CPUs remained ahead but the Core i5 2500K saw a 14% hit to the performance in the benchmarks ran with the default mitigations. The Core i7 2700K and i7 3770K each saw around a 14% hit to the default mitigated performance as well but that extended to 18~19% if disabling Hyper Threading in the name of security. The AMD FX CPUs saw minimal change to performance with their relevant Spectre mitigations.