Hacker News Reader

Comment by ams6110 | Hacker News Reader

Honestly I'd be happy if they could stop Windows 10 from turning my laptop into a hair dryer randomly while it is otherwise entirely idle. The thing is sitting there doing nothing, suddenly the fan will start roaring and the CPU utilization spikes.

View on HN

Apparently Windows 10 likes to use idle time to test the memory:

http://superuser.com/questions/635837/high-cpu-load-from-sys...

In my desktop it was causing it to rev up the fan when it was idle for a few minutes.

Seriously why on Earth does this happen? Even if Edge ends up being more power-efficient the rest of the OS (Windows 10) is going to ensure that I will get no more than 3 hours of battery life on my laptop.

Windows update via svchost.exe has been the problem on the machines I support. I randomly eats 100% of the CPU for minutes at a time.

http://www.wintips.org/how-to-fix-svchost-exe-netsvcs-memory...

If I don't use a specific PC for around a week, it's basically unusable on startup. CPU/HDD are at 100% for around 20 minutes, then every now and then they spike again.

I dunno what the hell Microsoft are playing at, but I'm in the process of switching all my computers to Linux.

Well, that's one thing you can be sure will never happen with Linux/*BSD. If some service bothers you, you can always reschedule it or turn it off. Good like with "phone home" updates in Windows 10! (unless you are an enterprise user, and even then...)

It's a poorly programmed code of the Update subsystem, and I've located the problematic function spending all of the CPU time:

https://news.ycombinator.com/item?id=11267019

     wuaueng.dll!CUpdatesToPruneList::AddSupersedenceInfoIfNeeded

The bug is obviously in highly inefficient traversal through the existing info about the updates, which didn't degrade to being so obviously bad at the time when there was just a small number of the updates.

I've used Microsoft tools to diagnose that, and I'm not the only one who has found it,

http://www.dslreports.com/forum/r30535980-WIN7-MS-updates-ta...

so the same info is available to Microsoft, but they obviously don't want to fix it.

On my machine it takes some 4 hours using 100% CPU of one core. If there are only 100 millions of such machines, and if it's just 40 Watt hours used during these 4 hours, it gives some 4 Gigawatt hours wasted every month in the world due to that particular bad code (If I calculated it right, over one year, it's a rough equivalent of the total energy use of 1500 Germans or 500 US citizens.)

The only solution to this I've found is to disable Windows Update from searching for updates by setting it to "Manual Updates Only".

However, this causes a problem in that every time you want to actually update, Windows Update may rebuild the entire "installed updates" database from scratch which can take hours on a heavily patched machine.

It's not related to the rebuilding or not rebuilding the "SoftwareDistribution" database (I've tried that) once the new updates exist, the traversal part is always slow, at least on Windows 7.

(The database is, fascinatingly, the whole 1 GB big).

I'm not certain what causes it for you, but for me it was microsoft's antimalware scans. These are supposed to run only in 'idle' mode but for whatever reason were running while I was using my computer.

What's worse is the automatic OS restarts that seem to also think I'm in idle mode.

If you're using Windows 10, have you set your active times?

I ended up turning off all that crap eventually. I cant remember what exactly I did but it was quite an adventure that involved registry edits and stopping services. Certainly not something that is made easy.

The setting I'm talking about is in Update Settings -> Change Active Hours. From your previous post, it sounds like you haven't disabled automatic updates, so changing when they update so it doesn't happen while you're working might be a good option, and it has nothing to do with the registry.

If you're on Pro or above you can set updates to download on demand

CPU? Never had problems with it.

But it literally rapes my HDD while updating(anytime it wants) or it's AV scanning disk(and you can't turn it off)

It makes my desktops unusable.

> The thing is sitting there doing nothing

Doing nothing, except mabye mining a fuckton of data about you and sending it to Microsoft.

To all the downvoters, please check this link: http://cmdrkeene.com/psa-windows-10-high-cpu-usage

And take note of point 1 and 2.

Reply on news.ycombinator.com