The Performance Hit For A Xeon-Backed Ubuntu Linux VM With L1TF / Foreshadow Patches

Last week L1 Terminal Fault (a.k.a. L1TF and Foreshadow) was made public as the latest set of speculative execution vulnerabilities affecting Intel processors. This Meltdown-like issue was met by same-day Linux kernel patches for mitigating the problem and does introduce another performance penalty but in this case is at least only limited to virtual machines. Last week I posted some initial L1TF-mitigated KVM-based VM benchmark results using a Core i7 CPU but the results for sharing today are using a much more powerful dual Xeon server.