Game On...For Now
This first round of Meltdown and Spectre patch testing proved fairly uneventful. There really wasn't much to report across our suite of game benchmarks. But that's partly because the status of patches keeps changing. We originally planned to test with both the operating system and microcode updates for Spectre Variant 2, which are expected to impose a significant performance overhead.
Unfortunately, Intel and its partners pulled the microcode patch during our testing, and AMD still doesn't have a fix of its own. We've been told that Intel's updated update is undergoing rigorous validation, but we don't have a time frame for its release. The same goes for AMD's Variant 2 microcode. Of course, we'll add test results with the new patches once they are available.
For newer processors, it looks like the operating system patch won't affect gaming workloads much, if at all. Most games are confined to the user space and don't make frequent kernel calls, so it's possible that the impact on older CPUs could be minor as well (game testing on those is in-progress).
The current patch does have an impact on storage performance, at least when it's measured with synthetic benchmarks. A laggy hard drive would obviously affect level loading times and the storage subsystem's ability to feed the game engine, possibly resulting in choppy scene transitions. We scrutinized our load times and cut scenes closely, and while entry-level CPUs did take longer and were less smooth, it's hard to chalk that up to a security patch because slower processors are, well, slower. We didn't notice any dramatic changes in performance consistency or frame time variance, so any minor impact would likely be limited to storage-imposed symptoms, at least with the patches as they sit currently.
Most of the vulnerability-oriented storage testing we've seen is happening at high queue depths, or using pure read or write workloads that aren't the best indicator of operating system performance. Most real-world accesses occur at lower queue depths, and radical changes in SSD performance, either for better or worse, don't correspond linearly to application performance.
The Spectre Variant 2 patches still loom large for Intel and AMD. Hopefully, both companies can deliver solid updates with minimal impact. We've heard that some applications can be optimized to minimize overhead. And Intel has mentioned that existing patches will mature into more efficient implementations.
For now we remain vulnerable to Spectre Variant 2, and proof-of-concept code is already popping up in the wild, unfortunately. That leaves us exposed while we wait on Intel and AMD, not to mention the rest of the industry, to correctly patch what could be the greatest vulnerability of our time. At least we can enjoy some gaming while we wait.
MORE: CPU Security Flaw: All You Need To Know About Spectre
MORE: Best Gaming CPUs