Intel Processors may see a 5-30% performance hit soon.

[Jerad]

So a Co-worker just shared this with me today: https://www.theregister.co.uk/2018/01/02/intel_cpu_design_flaw/

Looks like a security bug for pretty much all Intel processors is going to have to be patched out at the OS level that is going to cause them to take a substantial performance hit. AMD isn't affected by this either, which might give Ryzen (and potentially Ryzen 2) a that little boost to out perform Intel at a single core level.

I am wondering how much of an affect it will have on all the different game servers out there right now. Could be seeing a lot of poorly performing games in the near future.

Edit: upon further reading, it appears the desktop performance drops are minimal so far and some of the larger performance hits are in database apps.

 

[ShadniX]

This will probably effect everything that is using a lot of syscalls. In regards to games, it should be at least whenever something is being read from the disk (loading at the start and while playing). I have no idea if draw calls to the GPU are using syscalls. If yes... oh boy...

 

[Brainling]

Draw calls do not require a kernel page table look up, no. At least not in the modern Windows driver architecture. A lot of that got moved out of the kernel and in to user space specifically for performance. There are still some syscalls involved with the GPU but mostly hardware enumeration and handle creation.

The initial benchmarks post-patch are showing no appreciable changes in frame rates. There are a few games, like Witcher 3, that have taken a hit because they constantly stream in level data, which does require syscalls. There is talk about allowing gamers with a lot more RAM to setup pre-caches for that kind of stuff so that the game doesn't need to make a syscall to read the data, it can stream it from a RAM cache which is filled in the background. For people like me with 32GB of RAM that works out. It's not a universal solution though. That said, for people who's machines could already beast Witcher 3, the difference is imperceptible unless you are specifically looking at your frame numbers. Going from 110 FPS to 100 is not noticeable to most people. It's people who were already at the fringes of performance, just barely scraping up 60 FPS, that are going to feel it.

If you have a very modern CPU (Skylake, Kaby Lake, Coffee Lake) it has a feature called PCID that helps alleviate a lot of the performance issues...but that doesn't mean a lot to people holding on to old Sandy Bridge and Haswell era processors that they've previously had little reason to update.

And AMD is not effected by Meltdown, but they are absolutely affected by Spectre which is a different vulnerability. AMD is not free and clear on this. Really no one that uses branch prediction (e.g. everyone) is.

 

[Kenadian]

Do I need to worry if I'm on an IvyBridge? As it is streaming and playing The Witcher 3 is close to not possible so this could be the tipping point for me.

Also I'm on Windows 7 and have not installed the update at this time.

 

[Brainling]

Hard to say. IvyBridge is definitely one of the CPU's without the fancy PCID instructions to lessen the impact. I know Microsoft has said Windows 7 and Windows 8 will notice a much larger impact than Windows 10, because they do a lot more with kernel page table munging than Windows 10 does (a lot of stuff was moved out of the kernel in Windows 10 for unrelated reasons).

My guess it may hurt your performance yes, but whether it makes it unstreamable I don't know.

 

[Jerad]

Initial benchmarks seem to make very little impact for desktop users with most PC's seeing a 0-3% drop in fps. Not sure if anyone has done any through testing on the impact for streaming yet though.

On the flip side the major performance impact is on the server end of games most notably Fortnite seeing massive performance issues after the servers were updated with the Meltdown and Spectre vulnerability patches last week.