Intel recently released information about the Downfall vulnerability that affected multiple generations of proprietary processors. The company has released a firmware update that partially fixes the vulnerability, but there have been concerns about decreased chip performance with AVX2 and AVX-512 workloads.
The demise is affecting Intel consumer and server processors from Skylake to Rocket Lake — most “blue” chip users faced a hypothetical threat (except for owners of the latest models). resource Phoronix I decided to evaluate in practice the impact of the patch on the operation of three processors in a Linux environment: servers Intel Xeon Platinum 8380 (Ice Lake) and Xeon Gold 6226R (Cascade Lake), and consumer Core i7-1165G7 (Tiger ). Lakes were selected for the test. Software with Intel oneAPI support was used.
The Intel Neural Magic DeepSparse 1.5 and Tencent NCNN AI platforms and the QMCPACK system experienced a 17% drop in performance. The Intel Xeon Gold 6226R performed similarly, losing up to 33% in OSPRay 2.12 and up to 20% in Neural Magic DeepSparse 1.5. The consumer Intel Core i7-1165G7 dropped 11% in OpenVLK 1.3.1 and from 19% to 39% in OSPRay 2.12.
The AVX2 and AVX-512 workloads are not only present in AI and HPC, but also in mundane tasks like video encoding, which is a bit depressing. On the other hand, Intel has made the downfall protection optional. It is quite difficult to exploit this vulnerability and it is especially dangerous in the cloud environment. Therefore, everyone has to answer for themselves the question of which is more important: speed or security.