• MDS / Zombieload Mitigations Come At A Real Cost, Even If Keeping Hyper Threadin
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https://phoronix.com/scan.php?page=news_item&px=MDS-Zombieload-Initial-Impact&fbclid=IwAR3avya9MgbYZHBt16x4fg20QvFb1U0CuyPKb3zUOS8APDS4e6TpsnT3SJU MDS was announced on Tuesday and I am running a number of MDS/Zombieload mitigation benchmarks including the likes now of comparing the overall Spectre/Meltdown/L1TF/MDS impact and also if going the "full" route of disabling Hyper Threading. Tomorrow will be the first featured (multi-page) article with MDS data on multiple systems while here are some initial numbers I am seeing when just looking at the new default cost of this MDS mitigation. https://files.facepunch.com/forum/upload/58146/eab71fb7-bbd2-49ec-ad2c-5d23ff957de4/imagen.png Essentially, after the mitigations, the 7980 takes 4x times more than the 2700X to do a context switch :v
Oh my god, it's like everything AMD needed to gain back popularity has happened in the past few years
AMD: At least our CPUs are secure.
I understood some of those words.
Is it the time for Intel to rename their CPU's so we can see tests titled Intel Fallen i9-xxxx vs AMD Ryzen 3XXX?
What are the real risks for a gamer to disabled all those fix to keep the original performance ? For a server I understand it's a no go. But for a computer used mainly for gaming with an up to date antivirus and protected behind a nat wouldn't the risk counter the loss in performance ? I'm using a ryzen btw so I don't really care about those last patchs.
Honestly I have no clue what most of those graphs actually mean. I can see how it can affect some programs and tools that are used on servers or special application, but there is little in the article that says how much it really is. How much is 0.46us Per Event more actually hurting in the OSBench File Creation benchmark etc. Makes me wonder what the "real cost" for regular users is, with more "normal" workload like games, content creation etc. But thats not the target of the article.
I'd say it's a bigger risk for end user machines than anything else, because a lot of these exploits can be done from javascript.
You have to disable certain hardware functionalities of your CPU to avoid big exploits Intel recently found. However, disabling those functionalities forces the CPU to take the long way to do things. The CPU has to take more cycles (ticks of the quarts clock that keeps everything in time) to do simple things like loading a new program in to do work on it (which is what we call context switching). Those extra required cycles add up really fast.
For now, both Intel and AMD prioritize performance over security
You're probably better off not disabling the patches. From what I understand about these vulnerabilities, the thing is that the fixes only affect the security-critical parts of code like system calls and context switches, where it's crucial that no data is allowed to leak to another process. If you have a computationally heavy app that does most of the work by itself without interacting much with the rest of the system, it shouldn't get affected much by these fixes. Things like virtual machines and servers are gonna get hit the hardest by the patches. In fact, Phoronix have done some extensive tests covering all sorts of use cases: https://phoronix.com/scan.php?page=news_item&px=Zombie-Load-Gaming-Impact Barely any effect in games. https://www.phoronix.com/scan.php?page=article&item=mds-zombieload-mit&num=1 More general tests just for the latest patches and all the vulnerabilities combined. Intel often sees a combined 15-20% performance drop, but that's mostly in applications an average home user wouldn't really touch. If you're just encoding video, running photoshop or whatever, you probably won't notice a big difference.
I wonder if this will impact the machines at my workplace. Might cause a headache, dealing with the Spectre and Meltdown patches are causing issues enough as it is lmao
I want to see how this actually affects performance in an actual average use case.
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