Something Called "NET. Runtime Optimization" Using 100% of my GPU When Idle.

Status
Not open for further replies.

Hendlton

Estimable
Aug 15, 2014
22
0
4,560
I noticed my fans were really loud when I left my computer for a while, checked SpeedFan and yup: https://imgur.com/TOuhqPp Something was putting a load on my CPU and GPU. I left it alone with Task Manager open and it showed something called NET. Runtime Optimization using 100% of my GPU and about 50% of my CPU. Google comes up with a million results for high CPU usage, but I don't see anyone complaining that NET. Runtime Optimization is using their GPU. So I assume it's some kind of malware, mining bitcoin on my PC, but Malwarebytes comes up with nothing. I did a normal scan and scanned for rootkits. It also disappears as soon as I move my mouse, so I can't easily look into it. I tried Process Monitor to see if anything else is going on. It shows mscorsvw.exe using the CPU. But, again, Google tells me mscorsvw.exe puting a load on the CPU is normal. That still doesn't explain why my GPU is at 100%. What else can I do?
 
Solution
Perhaps an undetected miner of some type....

back up what you need, and 'nuke it from orbit', then full reinstall....

It is giving classic behaviour of other sophisticated miners, trying to avoid you noticing it...

Even if not a miner, whatever glitch it is will most certainly be taken care of with a full reinstall....

bigpinkdragon286

Distinguished
Oct 3, 2012
229
0
18,910
Old Microsoft blog post explaining the behavior.

It's not a virus or malware, it's just a background process that is precompiling .NET assemblies. This has to be redone from time to time as changes to the .NET environment takes place through patching and new versions.

The priority level is typically low, so while it may use the CPU up to 100%, tasks that you run will preempt it.

Still, the best thing to do is just leave the machine on to finish the task and then it shouldn't bother you again for a while, such as weeks, months, or longer.
 

Hendlton

Estimable
Aug 15, 2014
22
0
4,560


It's not a problem, other than power consumption, because it doesn't even do anything while I'm at the PC. It only happens if I don't move the mouse for more than 15 minutes. I Googled, like I said, and it also suggested it would do its thing and eventually stop. but I have left my PC idle for hours over the last few days and it still does that every time. I'm assuming it shouldn't take that long, should it?
 

bigpinkdragon286

Distinguished
Oct 3, 2012
229
0
18,910
There is no set time limit for the process. It will run until it's finished processing .NET binaries. Two immediate factors would be the speed of your machine and the number of binaries your machine has that need processing.

If it doesn't stop after a week, maybe I would become concerned.
 

Hendlton

Estimable
Aug 15, 2014
22
0
4,560


I've got an FX 6300 which isn't the best, but it seems to be using the GPU which is a GTX 1060. It shouldn't be taking too long. I guess I'll report back in a week.
 

Hendlton

Estimable
Aug 15, 2014
22
0
4,560


Well, it's 10 days later and it still happens when I leave my computer idle. I left it to do its thing for at least a couple hours every day, but I come back to loud fans and high temps every time I leave my computer. I also noticed it didn't happen when my internet cut out for an hour a few days ago, but I'm assuming that's normal either way.

The link you provided also leads to this:

https://blogs.msdn.microsoft.com/dotnet/2013/08/06/wondering-why-mscorsvw-exe-has-high-cpu-usage-you-can-speed-it-up/

which says that it can be sped up by running some commands. I tried and it says "All compilation targets are up to date."

At this point I'm thinking I should set the computer to go to sleep after 15 minutes of being idle so it doesn't just sit there at constantly high temps. I'm guessing that doesn't do much good for the longevity of the GPU.
 

mdd1963

Distinguished
Perhaps an undetected miner of some type....

back up what you need, and 'nuke it from orbit', then full reinstall....

It is giving classic behaviour of other sophisticated miners, trying to avoid you noticing it...

Even if not a miner, whatever glitch it is will most certainly be taken care of with a full reinstall....
 
Solution

Hendlton

Estimable
Aug 15, 2014
22
0
4,560


I nuked it and it seems to be fine now. Thanks for the help.
 
Status
Not open for further replies.