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What is your experience?
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pacman -S spotify-launcher
mount /dev/disk/by-...
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I haven't noticed any, but I don't do anything that stresses the CPU. Phoronix has run a lot of detailed benchmarks in the last few days...
https://cse.google.co.uk/cse?cx=partner … gsc.page=1
Last edited by Slithery (2018-01-07 16:32:57)
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https://www.epicgames.com/fortnite/foru … ity-update
The following chart shows the significant impact on CPU usage of one of our back-end services after a host was patched to address the Meltdown vulnerability.
https://i.imgur.com/h2KcUlE.png
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Metldown Patch on Linux - Interrupt Activity
Last edited by ugjka (2018-01-07 17:03:31)
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paru > yay | webcord > discord
pacman -S spotify-launcher
mount /dev/disk/by-...
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I'm afraid to update the kernel because I run Windows 10 in a VM with pci passthrough so I can play Windows games without having to dual-boot. I wish I had some solid numbers to know just how bad it'll be.
R.I.P In Pieces
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I'm afraid to update the kernel because I run Windows 10 in a VM with pci passthrough so I can play Windows games without having to dual-boot. I wish I had some solid numbers to know just how bad it'll be.
you can turn it off via kernel paramters nopti or pti=off
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Sorry, but not to closing a big security hole because of a few FPS (it really shouldn't be much) is a bit stupid.
Last edited by Thorsten Reinbold (2018-01-07 18:15:23)
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I'm afraid to update the kernel because I run Windows 10 in a VM with pci passthrough so I can play Windows games without having to dual-boot. I wish I had some solid numbers to know just how bad it'll be.
Ah, but the next logical question is, what are you going to do about updates to the Windows 10 kernel?
Nothing is too wonderful to be true, if it be consistent with the laws of nature -- Michael Faraday
Sometimes it is the people no one can imagine anything of who do the things no one can imagine. -- Alan Turing
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How to Ask Questions the Smart Way
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you can turn it off via kernel paramters nopti or pti=off
That's good to know, guess I should update then.
Ah, but the next logical question is, what are you going to do about updates to the Windows 10 kernel?
Cry
Last edited by thatnewyorker (2018-01-07 18:32:45)
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OK, good news folks — I've just had a quick blast of CS:GO with the page table isolation in effect and the framerate seems undiminished (as measured by cl_showfps 2), AFAICT.
EDIT: Intel Haswell (HD4600) laptop.
Last edited by Head_on_a_Stick (2018-01-07 19:09:15)
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Sorry, but not to closing a big security hole because of a few FPS (it really shouldn't be much) is a bit stupid.
Is it runtime switchable?
(If you're sure not to run external code, eg. no browser process etc., it'd be justifiable to temporarily switch it off when gaming - a few FPS can make the difference between playable and stuttering. Though afaiu gaming performance shouldn't be notably impacted anyway by the nature of games and this bug)
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Regarding to some benchmarks on phoronix, the impact in gaming performance is going to zero. Seriously: There's no reason to panic.
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Is it runtime switchable?
@seth not currently https://www.spinics.net/lists/kernel/msg2691093.html
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I ran a quick test which involved doing tons of syscalls inside a for loop and the performance drop was pretty much noticeable even with pti=off.
Linux 4.14 unpatched: 4.100s (avg)
Linux 4.15 w/nopti: 4.800s (avg)
macOS with meltdown patch: 12-14s (same hardware)
You might want to check this out. Usage: time ./test
#include <unistd.h>
#include <sys/syscall.h>
#include <stdio.h>
int main(void)
{
long value;
for (int i=0; i<100000000;i++)
value=syscall(SYS_getpid);
printf("%d\n",(int)value);
return 0;
}
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I ran a quick test which involved doing tons of syscalls inside a for loop and the performance drop was pretty much noticeable
In fairness due to what KPTI is it was always going to add some overhead to syscalls, so a test that just does them over and over was always going to be slower. While this is a useful benchmark, it doesn't tell us much about how the patches affect day to day / real usage.
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I'm using an apollo lake n4200 cpu and I don't really notice any significant change in speed as per my day to day activities. I remote into a windows machine when I want to do some light gaming but to be fair it's an AMD machine that wasn't all that powerful to begin with. An fx8320@4.2Ghz + 750ti.
All in all, I'm just glad the patches are out.
Of course, since patch source is visible, I wonder how long it will be before the patch code itself is attacked...
Last edited by exad (2018-01-12 04:05:22)
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What is your experience?
Before, my fans would rarely turn on when I wasn't compiling, recoding media, or running some programs that require lots of CPU. After all the patches, my fans turn on when I open my Youtube subscriptions page. They also turn on when I'm playing a movie. Yeah, it's not fun.
Please vote for all the AUR packages you're using. You can mass-vote for all of them by doing: "pacman -Qqm | xargs aurvote -v" (make sure to run "aurvote --configure" first)
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