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So-called upgrades that ruin good programs

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Stoic Joker:
Just some detail stuff:

It's a Dell Inspiron 1545 with 3GB RAM and a single core 2.20GHz Celeron.

Network Adapters:
Dell Wireless 1397 WLAN Mini-Card
Marvell Yukon 88E8040 PCI-E Fast Ethernet Controller

Strangely search behavior (speed) is quite good. Default is search everywhere (WT..?), and I gotta say I liked it much better when it spread the results over the entire screen instead of just the strip on the right ... Were they shooting for the worst of both worlds on that move??

If this post seems more appropriate as an entirely separate discussion or part of some other existing thread hopefully a mod will take care of that. I'll leave it to more organized minds to make that determination.  :)

At the risk of derailing this thread, for anyone experiencing a lot of problems in Windows 8.x with programs slowing down either routinely or randomly or even hanging for no apparent reason a few months ago I ran across a likely culprit. If you're using desktop compositing in Windows 7 it applies there as well. On my computer it turns out the common component for all of my "not responding" problems is the window manager - DWM.exe.

Warning: If taken internally the spoilered explanation which follows may induce headaches, blurred vision, nauseau, and vomiting.
If you experience any of these symptoms you are advised to stop reading and/or start drinking immediately.
You have been warned!

I actually stumbled across the answer entirely by accident when I was looking for replacements for Windows components. Specifically it was my choice to start using System Explorer as an alternative to the built-in Windows Task Manager. It turns out Task Manager conveniently omits DWM from the list of running programs and therefore doesn't tell you when it's hanging. Instead it will list other applications as not responding when in fact they are working correctly but waiting for the window manager to respond to some request.

The big problem in Windows 8 is that, unlike Windows 7 and Vista, compositing is mandatory because the Desktop is always composited on top of the Start Screen. Whereas Windows 7 gives you the option to turn off compositing by turning off all the Aero features (and potentially requiring you to turn off the DWM Session Manager service manually) there is no alternative window manager to use in Windows 8.

This has a number of implications for using compositing, whether in Vista, 7, or 8. The most problematic IMO is the impact your video driver potentially has on system performance. Since DWM is heavily reliant on advanced features of modern video cards, any video card driver problem potentially represents a system stability and/or performance issue.

If, like me, you happen to have a system utilizing integrated AMD/ATI video, that's particularly bad news. Prior to the introduction of the first Radeon cards ATI was arguably the model of stability and reliability. Since high performance video became essentially a 2 horse race between them and nVidia their driver development has turned into almost a primer in how not to support your hardware. In the case of outdated legacy products like my integrated Radeon 4250 (AMD 880g chipset) it's compounded by the expected (and normally not unreasonable) disinterest in anything beyond basic stability upgrades.

At least in Windows 8.0, there appears to be a mechanism in place for restarting DWM when it hangs. That's great in theory but in practice it seems to rely on explorer.exe to identify when DWM hangs and initiate the restart. In fact given the tendencies in Microsoft/Windows design I wouldn't be surprised if it is contained entirely in explorer. Without either a lot more analysis than I'm willing to perform that's nothing more than a guess on my part, albeit a somewhat educated guess.

I can explain how I discovered all this, though, starting as I said with using System Explorer rather than the Windows Task Manager to monitor processes. The first clue, which I didn't recognize immediately, was that explorer.exe appeared to be crashing a lot in Win8. I only noticed it happening when I had 2 or more file manager (or WTF ever they're calling Windows Explorer) windows open, but I never bothered to do much digging so it could have been happening in other circumstances without me noticing.

It's probably worth noting that one difference I've noticed between Win7 and Win8 (now that I'm paying attention anyway) is this. In Windows 7 if I restart DWM it doesn't appear to impact explorer at all. Explorer.exe seems to continue running resulting in my File Manager windows simply disappearing when the window manager shuts down and then reappearing when DWM starts up again. In Win8 I didn't get around to monitoring explorer.exe when I restarted DWM manually but it definitely killed all the File Manager windows.

I knew explorer.exe was significantly rewritten for Win8 because of the (IMO major step backwards) integration of the "Modern" UI (eg Start Screen) to ensure it would run at all times. Essentially that created the exact sort of monolithic code they've been removing and replacing for close to a decade. Figuring that to be a likely suspect in the problem I hypothesized that using a third party file manager might solve the problem. In fact that might be true if it's one of the more sophisticated (typically payware) alternatives with as few hooks as possible into explorer features like shell extensions.

However I was looking for something to recommend to Joe Six Pack which meant it should retain as much of explorer's File Manager features and if possible a very similar look and feel. For that reason, and various others, I settled on Explorer++. That did solve the problem of explorer crashing but replaced it with even more problematic behavior.

From time to time, and with increasing frequency the longer I went between reboots, Explorer++ would hang - or at least that's what the Windows Task Manager claimed. What was worse was that killing or restarting it from the Task Manager didn't work. I mean it worked in the sense that the process was definitely running but the window never appeared no matter how many times I killed and restarted it. Except I could get it to work by opening an explorer File Manager window and then using Open with... from the context menu to open a folder with Explorer++.

When I switched to System Explorer, though, I saw a very different picture. It didn't tell me Explorer++ was hung (ie Not Responding) but instead showed DWM was hung. That seemed to be the entire key to the problem since I could restart DWM and then restart Explorer++ and it worked normally. Just as importantly the time between DWM hanging seemed to reset to the longer period typical right after a reboot.

Or at least it worked most of the time. Eventually, though, I realized sometimes I could restart DWM and restart (or kill and then normally launch) Explorer++ and it didn't solve the problem at all. However if I restarted explorer.exe as well it always sorted the problem. My takeaway from all this - and let me repeat my analysis was incomplete - is that troubleshooting performance problems, especially program hangs, requires an alternate task manager. Additionally it's entirely possible, if not extremely likely, chance the shell (explorer.exe), window manager (dwm.exe), and video driver may be involved.

If you are having performance issues in Windows 8.x don't rely on the Windows Task Manager to tell you where the bottleneck is. There's a not-insignificant chance the window manager is at least partly to blame and a 100% chance Task Manager will blame any program waiting for the window manager if that's the case.

System Explorer will definitely show you more reliable information. Some or all other third party process monitoring/management software may be just as good or better. As a last resort restarting dwm.exe (the window manager) and/or explorer.exe (the shell) may temporarily fix performance issues. Due to the mandatory compositing of the window manager the video driver may be part of the problem and/or solution but if it's old enough hardware you probably shouldn't hold your breath.

Upgrade of Google: staff of Google have properly thought to move the item "Video" into a deep structure. Now to reach "Video" it takes four clicks instead of two.

(there is still the old good page at but I am sure it will be deleted)


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