Storage Tests and Conclusion
The final set of tests I’ll be looking at are storage benchmarks, because it’s here where we saw the biggest impact on the desktop platforms. It’s a similar story on both the PCIe and SATA SSD equipped laptops, with massive reductions in performance seen in nearly every situation.
The 8th gen XPS 13 with a PCIe NVMe SSD suffers significantly in the sequential write test, with a performance decrease of 24 percent, whereas the 5th gen XPS 13 with a SATA SSD is largely unaffected.
With queue-2 1-thread random performance, though, the 8th gen system takes a 5 and 15 percent hit in reads and writes respectively, whereas the 5th gen system gets punished with 18 and 39 percent drops.
It’s interesting to see how other queue depths and thread counts affect performance. With 8-thread, 8 queue depth random transfers, the 8th gen system takes a 14 percent hit in both reads and writes, while the Broadwell machine takes a larger 34 percent hit in reads but the same 14 percent in writes.
And then switching to a single-thread random transfer with a queue depth of 32, and the SATA drive gets punished with a more than 40 percent reduction in performance, compared to 35 and 12 percent drops in reads and writes respectively on the PCIe drive.
In the end, the performance impact of the Meltdown and Spectre patches is a bit more severe on laptops with an Intel U-series CPU inside compared to the desktop platforms we looked at earlier.
On the desktop, most productivity workloads saw performance drops that were within the margin of error, or a few percent at worst. However on both the Kaby Lake Refresh and Broadwell laptops we looked at today, almost every workload was impacted by an amount that’s too large to attribute to a simple margin of error.
Workloads like Cinebench, x264 encoding, Excel, Adobe Premiere, Photoshop, and MATLAB all experienced noticeable performance declines typically around the 5 percent mark, though the worst case was a 19 percent drop in Photoshop on the i5-5200U. Other tests like PCMark, Handbrake, 3DMark and both compression and decompression were largely unaffected.
One of the more interesting things to note from these benchmarks is there doesn’t seem to be a significant difference in the amount of slowdown between the three-year-old Broadwell laptop and the modern Kaby Lake Refresh laptop in productivity workloads. It’s certainly not a situation where the older and slower Broadwell is affected more than newer parts, in some situations the 8th gen parts are hit harder, while in others 5th gen suffers more.
Of course, storage performance declines significantly on both systems, particularly the write performance, though that isn’t surprising considering what we saw on the desktop side of things.
We’ll continue to monitor the situation with the Meltdown and Spectre patches, especially as an already worrisome and complicated matter is turning into a big disaster for Intel -- security issues aside -- in rushing a fix for the Spectre flaws, the company has discovered and now identified that the current microcode update is causing random crashes and other instability problems on a variety of hardware, old and new.
Based on this information, Intel is now advising OEMs to pull their Spectre BIOS updates until a newer release is tested and distributed. There have also been reports that the updates don’t even fix the vulnerabilities. Meanwhile, Google is coming to the rescue by offering a software solution that they claim not only patches the security holes but come at negligible impact in performance.
No doubt we'll be seeing even more updates to try and lock down these issues in the coming weeks and months, and we’ll be letting you know if any of them further affect (or fix) performance.