Ewww so they are doing all that context switching regardless then..confirmed at phoronix with linux benchmark.
Initial Benchmarks Of The Performance Impact Resulting From Linux's x86 Security Changes - Phoronix
The pity thing is that apparently if the OS patch is applied, this patch also affects AMD rigs performance, although AMD CPU are not affected by the breach security that is supposed to be worked around by OS patch. Thus, AMD recommends to not apply patch...
Bad 2018 start for Intel.
Maybe intel is already paying off the medias to shut up?How is it that none of the other major outlets have not reported this yet? Theregister.co.uk is not where I expect to see this type of news first.
I doubt it--the TLB hit is essential to the workaround, and is what it is.I have a feeling this is going to be something where we see a rushed patch then performance improvement over time.
AMD says to not apply the patch to computers using their CPU. So for this time, they might get away with better performance if the patch is optionally not applied.Unfortunately for AMD, they're probably going to get thrown under the bus with Intel as most OS providers appear to take any x86-64 platform and consider it unsecure. AMD has been lobbying for Linux to put in an exception for them, but it has not been accepted.
As for Microsoft, I figure they're going to take the simple path and do the same. Which means the hit that Intel takes, AMD is going to take as well (and in some cases, it might be worse if they're optimizing towards Intel as the target platform).
Just as an example, OSX 10.13.2 was patched for KPTI in early December, 10.13.3 is going to have additional tweaks.I doubt it--the TLB hit is essential to the workaround, and is what it is.
From what I've seen you can command-line bypass the changes in Linux if you're using a AMD processor, I just don't know if Microsoft is going to be so amenable. We can probably dodge the initial patch (if truth be told, this coming Tuesday), but imagine at some point there will be some mandatory security roll-up that will also include this. It'll become a fun game of "dodge the patch" for those AMD systems if it is to be avoided.AMD says to not apply the patch to computers using their CPU. So for this time, they might get away with better performance if the patch is optionally not applied.
But future O/S vers that would have the patch built in if there is no exception to not apply the patch then they would be hit as well.