Reviews of AMD’s Zen 5 processors this week surprised many, with lower-than-expected results. After some investigation, we discovered that turning off Simultaneous Multithreading (SMT) can yield notable performance gains, particularly in gaming. This article presents our findings, including comparisons with the 7800X3D and 7700X with SMT turned off.
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it’s obviously a scheduler/p-state bug in windows, look at the Linux performance
https://www.phoronix.com/review/ryzen-9600x-9700x
so, basically, the os isn’t tuned for the new chips yet.
the 2nd threads on smt-enabled cores are supposed to get hit last.
It’s an easy fix, sure.
But there are 3 manufacturers for them to schedule for. It should be ready way before anything ships.
Copilot and ads taking up development cycles
Actually, yeah, probably. CPU scheduling isn’t the shiny new thing, nor something that gets that sweet, sweet monthly recurring revenue. So, it doesn’t get prioritized.
Microsoft always operates like this. Whatever bullshit management demands for marketing purposes takes the resources away from basic stability and quality improvements. Sometimes this results in quite predictable disaster:
Microsoft Chose Profit Over Security and Left U.S. Government Vulnerable to Russian Hack, Whistleblower Says
There should be no need for tuning, tweaking, or optimizing on functionality this basic.
If you ask the processor, it will spit out a graph like this telling you what threads/cores share resources, all the way up to (on large or server platforms) some RAM or PCIe slots being closer to certain groups of cores.
For values of “new chips” that include 20 year old ones. Foster was released 2001, the chips were single-core but you could have up to eight on a board so it’s still multi-core SMT. First on-die multi-core SMT seemed to have been Paxville, 2005.
Or maybe Windows server has a proper scheduler and they never bothered bringing it to desktops?