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Vbox memory usage is much more than allocated
Posted: 7. Jan 2015, 06:52
by J-H-J
I have used vbox for a long time , but recently I found a problem
I created a virutal machine with windows xp installed, and I allocated 2GB memory.
My host system is Windows 7 x64 Ultimate, Vbox version is 4.3.20

- vm profile
- profile.jpg (73.46 KiB) Viewed 3549 times
When I had not powerd it on , below was my memry usage.

- Powered on
- poweroff.jpg (83.34 KiB) Viewed 3549 times
When I powered it on, below was the memory usage

- Not Power on
- poweron.jpg (88.06 KiB) Viewed 3549 times
The virtual machine used 2GB memory nomally.
But After 2 hours, things was completly changed,my host memory used up to about 7GB!
Re: Vbox memory usage is much more than allocated
Posted: 7. Jan 2015, 06:56
by J-H-J
Here is the memory usage after 2 hours

- 2 hours later
- poweron-2.jpg (87.41 KiB) Viewed 3548 times
Then I powered off the vm, the memory usage dropped to nomal.

- poweroff-2.jpg (87.42 KiB) Viewed 3548 times
How can I solve this problem, thks.
Re: Vbox memory usage is much more than allocated
Posted: 9. Jan 2015, 08:27
by socratis
Do you use shared folder and/or network shares to access files on the host? If yes, then it is not your VM that's using the memory, it's your host OS that is caching recently used files.
Re: Vbox memory usage is much more than allocated
Posted: 9. Jan 2015, 14:02
by mpack
Oh no, not again...
Re: Vbox memory usage is much more than allocated
Posted: 10. Jan 2015, 12:39
by J-H-J
socratis wrote:Do you use shared folder and/or network shares to access files on the host? If yes, then it is not your VM that's using the memory, it's your host OS that is caching recently used files.
Thks for your reply
This xp VM I created was for downloading video files, and it had a large amout of disk I/O(more than 10GB/hour).
I used share folders before to store files to a folder of my host system, but I found that it did not always work as expected, I often lost file access.
So I tried to use a VHD file directly attached to my guest system, and put my files to that VHD file.
Then I found my host system ran very slow after 2 or 3 hours, so I found that problem.
I know that my host system will cache files recently used, but these cached files will show as "cached" in my task mamager, and will not caculated as my used memory
You can see my last picture, it shows cached memory 3892, but my used memory is only 2.06GB.
Re: Vbox memory usage is much more than allocated
Posted: 10. Jan 2015, 15:48
by mpack
Seriously, I think we've had this conversation way more than enough times already. Search for those previous discussions. Google for more. In the meantime I'm locking this thread.