A Look At The CPU Security Mitigation Costs Three Years After Spectre/Meltdown

For I/O workloads is another area still prone to measurable performance degradation primarily for older Intel CPus with Retpolines for Spectre V2. For the newer Intel Comet Lake, Cascade Lake (and Ice Lake / Tiger Lake, albeit not tested in this article) should yield only minor overhead.

Depending upon the particular network benchmarks, the CPU security mitigations can still yield a measurable difference with the default mitigations even for the newest x86_64 processors.

The WireGuard secure VPN tunnel that has become increasingly popular over the past year or two with continued multi-OS support, mainline support in Linux and other kernels, etc, sees the largest hit on the older Intel processors. The newer AMD CPUs with Retpolines still sees a difference as well.