'Phoronix has conducted a series of tests to show just how much the Spectre and Meltdown patches have impacted the raw performance of Intel and AMD CPUs. While the patches have resulted in performance decreases across the board, ranging from virtually nothing to significant depending on the application, it appears that Intel received the short end of the stick as its CPUs have been hit five times harder than AMD, according to ExtremeTech. From the report:

The collective impact of enabling all patches is not a positive for Intel. While the impacts vary tremendously from virtually nothing to significant on an application-by-application level, the collective whack is about 15-16 percent on all Intel CPUs without Hyper-Threading disabled. Disabling increases the overall performance impact to 20 percent (for the 7980XE), 24.8 percent (8700K) and 20.5 percent (6800K).

The AMD CPUs are not tested with HT disabled, because disabling SMT isn't a required fix for the situation on AMD chips, but the cumulative impact of the decline is much smaller. AMD loses ~3 percent with all fixes enabled. The impact of these changes is enough to change the relative performance weighting between the tested solutions. With no fixes applied, across its entire test suite, the CPU performance ranking is (from fastest to slowest): 7980XE (288), 8700K (271), 2990WX (245), 2700X (219), 6800K. (200). With the full suite of mitigations enabled, the CPU performance ranking is (from fastest to slowest): 2990WX (238), 7980XE (231), 2700X (213), 8700K (204), 6800K (159).

In closing, ExtremeTech writes: "AMD, in other words, now leads the aggregate performance metrics, moving from 3rd and 4th to 1st and 3rd. This isn't the same as winning every test, and since the degree to which each test responds to these changes varies, you can't claim that the 2990WX is now across-the-board faster than the 7980XE in the Phoronix benchmark suite. It isn't. But the cumulative impact of these patches could result in more tests where Intel and AMD switch rankings as a result of performance impacts that only hit one vendor."'

-- source: https://hardware.slashdot.org/story/19/05/20/228218

Cheers, Peter