Intel Hyper Threading Performance With A Core i7 On Ubuntu 18.04 LTS

Following the news yesterday of OpenBSD disabling Intel Hyper Threading by default within its OS over security concerns and plans to disable Simultaneous Multi Threading for other processors/architectures too, here are some fresh Intel HT benchmarks albeit on Ubuntu Linux. The OpenBSD developer involved characterized HT/SMT as "doesn't necessarily have a positive effect on performance; it highly depends on the workload. In all likelihood it will actually slow down most workloads if you have a CPU with more than two cores." So here are some benchmarks using a current-generation Intel Core i7 8700K six-core processor with Hyper Threading.

Others in the forum comments and elsewhere also characterized Hyper Threading as not having much of an impact these days compared to the days of just dual-core CPUs with HT. Since I haven't done any Hyper Threading comparison benchmarks lately, I fired up some overnight albeit on Ubuntu Linux rather than any BSDs simply for the maximum interest from our largely Linux audience. Tests were done on Ubuntu 18.04 LTS x86_64 with its default Linux 4.15 kernel.

Intel Hyper Threading was toggled from the BIOS/UEFI and aside from that it was a very straight-forward benchmarking process using the Phoronix Test Suite with a variety of workloads.