The saga of the cross-industry side-channel attack (Meltdown and Spectre) is not yet over. Turmoil continues as CPU vendors release new microcode and recall previous ones. To understand the extent of the work that still needs to be done, consider the language Linus Torvalds usesabout the patches sent by elite open source kernel developers to deal with Spectre — specifically “Indirect Branch Restricted Speculation.”
Development teams are left to sit back and watch as vendors struggle to decrease the performance impact of these fixes. For example, AWS claims “we have not observed meaningful performance impact for the overwhelming majority of EC2 workloads,” yet most big data workloads are heavily impacted.
Read more at The New Stack