For some reason, in the last few months I've been dealing with a spate of systems that are running slowly for no apparent reason.

I go through my normal routine of virus scans, disabling startup items, chkdsk, and other standard stuff, but it's still slow.

Pretty soon I started noticing something on the "Performance" tab in task manager. I've never really paid much attention to the disk usage meter because it's never been an issue before, but now I'm seeing all these instances of the disk getting pegged at 100% non-stop. Never letting up from the moment the computer is booted to the moment it's shut down.

I've done an absurd amount of research on this, and for the most part there have been a dozen suspected culprits, but I've settled on two:

Superfetch

This one is annoying because even on pages where people are insisting that it's the culprit, everyone is telling them to keep it turned on at all costs. I get that it's supposed to vastly increase performance by predicting user needs and loading things from RAM instead of the drive. But here's the thing. I've now seen three computers in the last two weeks where turning this service off decreases the disk usage immediately and permanently. The result is a computer that seems to work pretty normally. I think these people are all living in hypothetical land instead of the real world, but if you can think of a reason that I should re-enable this service on these computers, let me know, because it sure seemed to fix the problem.

Notifications

This one is weirder to me. I've now seen several Windows 10 computers where this helps. Under Start > Settings > System > Notifications, disabling all of them suddenly makes the disk usage go down to normal levels. I have no idea why this is the case, but it's worked for me.


I'm sharing this because I need to vent and I also want to make you folks aware of it in case you have family members who got force-upgraded to Windows 10 and now have performance issues. Tell me if I'm crazy

That's really interesting. I think that in both cases, those features normally should work without pegging disk all the time. I think that you're encountering a malfunction of some kind where turning off the services gets rid of the symptom, but the underlying root cause isn't fixed (whatever that is).

I could imagine a situation, for example, where some kind of settings which control those features are corrupted and cause the features to go crazy.

For instance, superfetch somehow get set to try to prefetch all files instead of just a selected set. I wonder how superfetch decides what to fetch, and if that's governed by a file somewhere on disk, and if that file is corrupted.

All good questions, Tony. And I agree, none of the solutions I've found or tried or even been successful with, feel like I'm fixing the problem. They definitely feel like I'm addressing symptoms. But in all my research I haven't seen anyone even hint as to what that might be.

In most cases, the best I can do is make the changes I've mentioned, and often that still results in more disk activity than I'd like, but easily in the usable range.

Looks like I'm OK, then...

tanstaafl.

Yes, that's what it should look like, and most people's systems do, particularly when they're not running much to speak of.

With these systems, I can open the task manager the moment after logging into Windows, and the disk is pegged to 100% and stays there permanently.

I have an update:

I ran into this very same issue again today, but this time the computer won. I tried the above solutions, as well as every single other fix I've read or thought about, and the disk is still pegged at 100% at all times.

I eventually left the computer with a chkdsk running because I had to get going. This one was super frustrating. Clearly Microsoft has a problem here, and I haven't seen anything to indicate that they know about it. I see a lot of different computers in my daily work life, and I've never seen anything hit so many systems at the same time.

The fact that it's happening so close together also has me wondering if it could be related to Windows Update. The anniversary update went out recently, and I wonder if there was something about that? I have no idea. At this point I'm just thinking out loud...

What does resource monitor show under the disk tab?

Nothing consistent. The top resource user changes fairly often. Sometimes it's just a rundll and other times it's just a system process. Other times it'll be Windows Defender (even though I've turned it off). But those are just some of the things that pop up and then go away. Other random stuff shows up in there too and settles back down. It's one of the things that's made tracking down the culprit so frustrating...

Anything happening simultaneously on the network?

Like what? Maybe. There's at least a dozen other computers in this office, but they all basically just go out to the internet for email and web browsing. This company doesn't do much on their computers.

BTW, I came across three more computers at a different location in the same company. The same or similar models. Makes me wonder if there's a driver issue. I tried calling Dell, but all they would say was that "these computers are not compatible with Windows 10." Yeah, well someone should have told Microsoft that when they forced the upgrade. How is the average user supposed to know? I really should have spent a week going around installing Never10 on all my clients' computers.

A long time ago I had a machine (would have been Windows 98 so say around 2000) that had some kind of hardware issue that caused it to keep interrupting. It showed up in Process Monitor (the Sysinternals one) under interrupts but you'd probably have seen noticed something like that. Replaced motherboard (no reinstall) and it was good again. Just throwing that one out there.

How is that even possible? Unless they are running a 16-bit 386 processor with 640K of RAM or something, how could they not be compatible?

tanstaafl.

BIOS, hardware drivers, older CPU instruction sets.

The idea that software or hardware 'updates' are optional or can be deferred or ignored is no longer valid. We are on an ever moving forward cycle of newer software requiring newer hardware, and the newer software is not optional. Security, stability, cloud services, etc all require the OS, drivers and apps to be maintained to 'current' versions. Endlessly.

Old hardware quickly becomes unsupported hardware. Unsupported hardware becomes risky hardware.

Buy or rent new hardware on a continuous cycle. The business, software and Internet architectures effectively demand it be this way.

I agree completely. Obviously, the Dell tech (tier 1, to be sure) was just reading off a script when he told me this. It's a default answer. He transferred me and I thought it was going to be a higher level, but after 30 minutes on hold it ended up being the gee-dee sales department. Ugh.

So I'm still looking for answers to this.

What Dell are saying is that they can no longer be bothered to support those computers. They've done no testing against Windows 10 (because it's not cost-effective).

They may or may not actually be "compatible with Windows 10". Unless you get a definitive statement from Dell that they actually tested the computers and found them not to be compatible, what the representative said is a lie.

I had a 100% CPU problem on my Windows 7 box last weekend. I used Process Explorer and WinDbg to figure out exactly what it was (a bug in Windows Update). A fix for that particular bug was included in an update rollup, but due to the aforementioned bug, it took nearly 12 hours to apply it, with the fan screaming like a banshee the whole time.

However, you seem to have a disk performance thing, so you probably want to throw some XPerf into the mix (not least because using WinDbg is emphatically not for the beginner or the faint-hearted).

OTOH, my default position with hard disk performance problems these days is simply to replace the disk with an SSD. That one change took the boot time (until usable) on Jen's laptop from 5-10 minutes down to about 10 seconds.

I'm going to try an SSD replacement merely out of curiosity. I'll then suggest it on the other computers that are having this problem. I'll be curious to see if it's still an issue after that. I wouldn't think so, but who knows? And in the worst case scenario, wouldn't hammering an SSD like that shorten its lifespan?

On the four Windows notebooks that I have had the misfortune of using ever so briefly, all of them had the hard disk pegged for the first 20min or so after boot/resume: anti-virus scan running.

Killing off AVG stopped the disk activity on the two I tried it on.

My first ever Windows notebook (well, not mine but one my client has loaned to me) shows similar behaviour, but the internal SSD means the continuous blinking (HDD LED) stops after just a minute or two.


Most of that activity is probably just "reads", so extremely unlikely. I'd think it would certainly shorten a mechanical drive's lifespan though.

Just wondering if there's a correlation between the CPU load, and network activity, in which case you might be able to narrow down the culprit by looking at what's being sent out over the network.

Ahh, my apologies. I misunderstood. I thought you meant traffic on the whole network, not just traffic leaving the computer. I don't think there was. I believe I tried disabling all adapters to test this (at this point I'm having a hard time remembering all the steps I tried).


I don't think that's it. We're talking about 100% for 100% of the time. They told me the computer had been slow like this for a couple weeks. I also disabled all AV programs, all non-MS services, and a bunch of other stuff.


Thanks! That makes sense.

Here's an update, and a possible explanation:

So I gave up on this computer last Thursday afternoon (I had other appointments and needed to get home). At that point, I left a chkdsk /f /r running because it was just taking so long. The user at that location reported that when the computer came back up, it wasn't much better, so they eventually swapped it with another less-used computer.

I followed up by going back to the location on Monday. When I got there, the disk usage was completely normal! The computer seemed quick enough and totally fine.

What I did notice was that the start menu had changed. It now showed the power, settings, and other icons as just icons (no text) shoved over to the left side. I believe this is the default for Windows 10 after the anniversary update.

The only thing I can think of is that these computers might be chugging away in the background on something as it tries to update the OS. I would have thought that the update would come through like any other one, where it downloads and installs, then does the bulk of the work when you restart the computer. But I'm not sure now. And if it is installing in the background, it's clearly not doing it correctly, and it's taking forever. I'm not sure what's going on and I wish there were some way to make MS aware of it. It's not like there's an error report box that comes up and says "I see your disk usage is unusually high - do you want to send an error report?" Heck, I've never really believed that those go to anyone anyway...

So that's where I am now. I haven't seen any real solutions to this problem, despite seeing people experience it all over as well as having experienced it myself over a dozen times.

They absolutely do. All of the reports are thrown into a massive database, some aggregation is run over them, and the most common ones are surfaced to the development team. Whether they bubble up the priority list to actually be addressed is entirely different, of course.

We used the Windows Error Reporting functionality at a previous employer (yes, it's available to third party developers), and it was invaluable for discovering customer problems before they reported them (or not) through the normal channels.

You know that "would you like to send more information?" question? That's also triggered by the developer marking a particular error report as "needs more information, can you grab me a full dump if it occurs in future?".

Ah, great to know Roger! Thanks for the info.

Unfortunately I don't know if there's a way for this issue to reach anyone in a position to fix it. Frustrating.