Benchmarking Linux With The Retpoline Patches For Spectre
First up are some of the synthetic disk benchmarks. With carrying out random reads with FIO, the Core i9 7980XE and Ryzen 7 1800X systems both saw a very noticeable drop in IOPS but the four other systems had not. The EPYC 7601 was equipped with the fastest NVMe SSD, the Intel 900p 2.5-inch drive, and it saw only a slight drop in performance when using the Retpoline kernel built under the patched GCC 7.2 compiler.
When enduring random writes with FIO, the Core i9 7980XE still saw a significant drop in performance but it was not as bad on the five other systems benchmarked.
With sequential writes, the Core i9 7980XE system was again the platform to see the most significant performance drop from Retpoline while the Core i7 8700K showed just a minor drop in performance and the other systems were flat.
The high-end Core i9 7980XE and dual Xeon Gold systems as well as the Core i7 8700K (Coffee Lake) saw drops in performance with Compile Bench when using the Retpoline-enabled kernel and further when built under the patched GCC compiler. The AMD systems saw only very slight decreases in performance as did the low-end Core i3 7100 Kabylake system.