An Early Look At The Linux 4.16 Kernel Performance With AMD EPYC
A few days back I provided some fresh Linux 4.16 kernel benchmarks compared to recent stable kernel releases while also toggling the KPTI and Retpoline security features on Linux 4.16 Git for seeing the impact of the Spectre and Meltdown mitigation techniques on this latest kernel while using Intel Xeon hardware. For this latest round of tests is a similar comparison while using an AMD EPYC system.
For this AMD EPYC Linux kernel benchmarking the following configurations were tested:
- Linux 4.14.0 stable that doesn't contain any Spectre V1 or V2 mitigation for the EPYC system.
- Linux 4.14.24 as the latest 4.14 stable point release at the time of testing that includes both __user pointer sanitization for Spectre Variant One and backported full AMD Retpoline protection for Spectre Variant Two.
- Linux 4.15.0 stable that contained full AMD Retpoline protection but that release hadn't offered any Spectre V1 protection.
- Linux 4.16 Git from this week offering both user pointer sanitization and full AMD Retpoline protection.
- Linux 4.16 Git from the same build but disabling the Retpoline support via the "spectre_v2=off" kernel command-line option. This though still leaves Spectre V1 protection in place.
All of this testing was done on the AMD EPYC 7601 32-core / 64-thread system built around the Tyan 2U EPYC server platform. Ubuntu 17.10 x86_64 was the base operating system.
All of these Linux kernel benchmarks were carried out in a fully-automated and reproducible manner using the open-source Phoronix Test Suite benchmarking software.