Google claims its Spectre patch results in ‘no degradation’ to system performance.
GOOGLE HAS CLAIMED that its patch for the Spectre CPU vulnerability results in “no degradation” to system performance.
Since the Spectre and Meltdown chip flaws were made public earlier this month, Intel and its partners have been scrambling to deploy patches to user devices.
However, many of the patches released have had a negative effect on CPU performance, with Microsoft last week confirming that its Variant 2 of Spectre could have “significant performance impact,” on some systems, especially those running Windows 7 or Windows 8 on older silicon.
Google is claiming, however, that its fix for Variant 2 (CVE-2017-5715), considered to be the hardest to patch without impacting performance, will have “negligible” impact on PC performance.
The fix, called ‘Reptoline’ uses software patches rather than disabling the affected CPU features, which Google claims resulted “in no performance degradation across the different mitigation techniques they have developed.”
“Retpoline sequences are a software construct which allows indirect branches to be isolated from speculative execution. This may be applied to protect sensitive binaries (such as operating system or hypervisor implementations) from branch target injection attacks against their indirect branches,” explained Retpoline creator Paul Turner.
“This confirmed our internal assessment that in real-world use, the performance-optimized updates Google deployed do not have a material effect on workloads.”
Google is calling for its Reptoline patch to be universally deployed in order to improve the cloud experience industry-wide.
Google VP Ben Treynor Sloss wrote: “We believe that Retpoline-based protection is the best-performing solution for Variant 2 on current hardware.
“Retpoline fully protects against Variant 2 without impacting customer performance on all our platforms.”
Intel, which after originally claiming that Spectre and Meltdown patches would not create any issues with computer slowdown last week said that impact will be “workload dependent”, has said that Google’s Retpoline technique “may perform better” than its own blended approach.
“Intel has worked with the various open source compilers to ensure support for the return trampoline, and with the OS vendors to ensure support for these techniques,” the company said.
“For Intel Core processors of the Broadwell generation and later, this Retpoline mitigation strategy also requires a microcode update to be applied for the mitigation to be fully effective.”
Source : Inquirer