What is dwm.exe And Why Is It Running?
You are no doubt reading this article because you are wondering why this dwm.exe process is taking more memory than you think it should, and you are curious what it does. Thankfully for you, we have the answer.
So What Is It Anyway?
Desktop Window Manager (dwm.exe) is the compositing window manager that gives you all those pretty effects in Windows Vista: Transparent windows, live taskbar thumbnails (that you can resize now), and even the Flip3D switcher that you can disable and replace with Switcher.
What happens in Vista is that applications write the picture of their window to a specific place in memory, and then Windows creates one "composite" view of all the windows on the screen before sending it to your monitor. Because Vista is keeping track of the contents of each window, it can add effects when layering the windows such as the transparency we're all used to, as well as the live preview thumbnails.
The benefit to using this approach is that Windows Vista can utilize the hardware acceleration features in your video card to create very smooth animations for minimizing and restoring, and even for the transparent effects.
What about Memory Usage?
If you open up Task Manager, you can see the dwm.exe process in the list, typically taking somewhere between 30-50MB of memory in my testing:
The size of the DWM process is controlled by the number of windows that you have open, since each window requires a buffer in memory to store the contents of the window. If you have a large number of very large windows open, DWM will use more memory.
The benefits of using a compositing window manager are worth that relatively small amount of memory under most circumstances.
Does Switching to the Vista Basic Theme Turn it Off?
The short answer is no, just switching to the Vista Basic theme will not turn off DWM, but it will reduce the memory usage a great deal.
How do you switch to Vista Basic? Just right-click on the desktop, choose Personalize, and then Window Color and Appearance:
Click on classic appearance properties at the bottom:
Then choose Windows Vista Basic and click the Apply button:
Note that I'm not recommending switching to the Basic theme, just explaining how to do it.
So How Do I Turn dwm.exe Off Then?
Note that I don't recommend turning this off unless you are playing games in fullscreen mode, and even then it likely won't help increase speed.
The only way to get rid of the dwm.exe process is to stop the service from running. Open up Services from Control Panel or the start menu, and then find the "Desktop Window Manager Session Manager" service in the list, and click the stop button. Note that you will be switched to the Vista Basic theme when you click the button.
To permanently disable it, double click on the item and select Disabled from the "Startup type" drop-down:
If you want to use the command line instead, you can open an administrator mode command prompt and use one of these commands:
| Stop Service | net stop uxsms |
| Start Service | net start uxsms |
| Disable Service | sc config uxsms start= disabled |
| Enable Service | sc config uxsms start= auto |
By now you should understand what the process does… do you really still want to get rid of it?
Thank you! I've been trying to figure out a way to get this worthless process gone forever!
why to save 50 MB of ram when I have 4gb in pc
@tomas
This series of guides is more about explaining what the processes are than anything else. I didn't advocate getting rid of the process, in fact I think I did the opposite.
Personally I love the new desktop window manager, I like how smoothly everything animates.
@The Geek, Do you recommend disabling this service if you only have Vista Home Basic?
Nice post !
I like the way you present things in an interesting way!
I'm impressed!
tomas,
You may have 4gb of mem in your pc, but unless you are running 64-bit Vista, not all of it is allocated or being used.
MY vista seems a little different from what you said in your instructions but I switched to basic and it just says under processes dwn.exe memory 1,484k….I have Vista business 2 gig memory chips,
What I would like to know is the paging file settings for using the cache as I am not certain of this…Ill ask on the forums I just noticed that.
thanks for your help
I love these guides to the processes that are running. Very helpful.
Who care? I have 8Gb RAM running on Vista x64 SP1..
Nice job of explaining dwm.exe to the average user.
Hmmm… I just did that (switched to classic theme) and it actually made dwm.exe run more of my memory…
It went from 21K to 34K memory. Sadness. The only difference btw the "theme" I was using was the background, but I was like, what the heck, let's see what it does. Stupid Vista…
:(
I find that by going to systems advanced and tick the box custom not let windows decide and then in settings un-tick all boxes and use windows standard or classic you get much more memory back
Oh just switch to XP, I'm pi***d off with Vista, it's slow, it churns your hard drive, I cannot access the features as easily as XP, sure it looks pretty but most people sacrifice the aero, flip 3d, and sidebar and turn off indexing because they find out that there cpu is runing at 80-99% and there hard drive looks like it's going to pack in at any moment trying to run them. The more RAM you put in your Vista machine, the more it uses. I have 2GB, used to have 1 and the machine still runs much slower than XP. I have dissabled the sidebar, left the pretty DWM on, dissabled superfetch (defrags your hard drive while you are using your computer - not healthy in my opinion) dissabled windows defender and firewall as I have kaspersky internet security that does all that and far better! Dissabled readyboost coz I don't use it. I turned off useless windows search coz that churns away at the memory, cpu and hard drive and because I very rarely loose a file that I create. And now my computer runs more like XP but prettier, it's now usable and boots up much better.
Thats my 2 pennies!
Thanx for this useful tip. Vista is a good OS but DWM itself is shitty useless feature. i dont need damn aero but faster OS. again thanx
What makes me wonder is why does dwm.exe regularly want access to the internet? I find that there are several of these types of things in Vista that want access to the internet when their function does not seem to imply any need other than patches or updates that should be taken care of in the regular way.
Totally agree with Paul Sumner's post (3 posts above this one), my experiences with VISTA are identical to his, indexing, superfetch, system restore, turned off, a whole load of services Bill Gates deems neccessary, that I did not need were disabled, Defender disabled, VISTA Firewall disabled, Security Center disabled, (I use Eset Smart Security Center, does a much better job using less resources) Windows Update disabled, UAC disabled, Sidebar disabled, yet I still had around 30 services running in the background. With VISTA at idle and with no applications open it was sucking up 550MB of my 2GB Crucial Ballistix DDR2 memory, thats over 25% of my memory gone just to keep VISTA ticking over.
Compare this to my XP-PRO SP3 set-up (I'm dual booting). 14 services running in the background, XP at idle takes just 96 MB of memory, and everything runs faster, applications open and run faster, gaming is faster, just about anything I want to do is faster on my XP partition.
If you want pretty looks use VISTA + Aero, if you want a fast system use XP !