moving machine / increasing size / registering moved install

[kardworx]

I am rarely this far in over my head but last time I played with this a lot it VMware back in 08 maybe, possibly earlier. I was backing up a FB game that is being retired. I set it up with the game running in a background tab with network disconnected but the game running, so you can restore the snapshot and the game is loaded for limited playing...
I now have this question for you guys:

I set it up with the default 8 GB of space, but to get all the game things I made a large number of snapshots. The folder for the VBox is 10.6 gb. The VDI is 6.4 GB, and the snapshot folder is 4.57 GB. This is way beyond the 8 GB space I allocated. This game might as well not be running at all it is so slow, but I think that could be that the Ubuntu install (11.10, I like that version almost as much as Hardy Heron) doesn't really have swap-file space. There is also the issue that the windows host can only give 128mb of video memory to this which probably also slows it down, it is a Flash-based game. So my question on this one is can I back the files up, remove VBox, reinstall, make a new machine with say a 15gb space allocation, and then drop the drive snapshots, VDI, etc that are there currently in the existing machine into the new machine? If I do this would it possibly increase the speed the game runs at by giving the machine swap-file space? I know that one is sort of complex but think you guys can point me in the right direction. I read or was told somewhere that once everything is moved to the new machine the uuid has to be registered in the machine? Is there a FAQ on doing that?

Thanks up front and peace-
Stu

[noteirak]

Few technical points about your current situation :
- The 8GB you set was for the disk size attribute. It does not set any maximum value for the VM folder. The maximum size of a VM folder is in the range of (Base disk size + (Base disk size * number of snapshots) + (RAM size * number of saved state)). So if you have a VM with 8 GB base disk, 10 snapshots and a 2GB RAM, you can go up to 110 GB of space. This is obviously a *very extreme* exemple.

- The more snapshots, the more files you will create to store the diff disks. so if you have 10 snapshots, you could end up reading from 11 files for 11 read/write requests in your guest OS. Quite nasty.

- I doubt a Flash game could use that much VRAM, but even so it wouldn't be your first issue.

Given all this, I think your general issues is to use many snapshots. How many do you have?

[kardworx]

I have 8 snapshots with a total of 702 mb between them. I gave the machine 1.5gb of operational memory. It could be it is slow due to video memory restrictions in VBox. So what do you think I can/should do to get this thing going better? And thanks, I really do appreciate your help here!

[noteirak]

Unless you can give specifics about your VM (see Minimum information needed for assistance), I can't give any recommendations.
128 MB VRAM is a lot of video memory. I harly see a flash game needing this much tbh, unless you can show me that it requires that much?

The slowness is most likely related to the snapshots with the I/O it generates, and possibly with your computer in general, but need the extra info to give a proper answer.

[mpack]

Much as I detest snapshots, I must mention that a long snapshot chain needn't involve more disk I/O than having no snapshots: except briefly, when opening the extra files of course. In normal operation the block table from each VDI is resident in memory, hence the I/O address resolution is a quick memory lookup and only one external I/O will be performed.

My first suspicion is that this VM is starved of disk space. Increasing the RAM allocation may actually have made this worse since it now has an undersized swap file, the disk being too small to accomodate a proper sized one. I would suggest ditching the snapshots, perhaps even start from scratch. Choose a single dynamic disk of reasonable size - say 32GB, and give the VM a reasonable amount of RAM, say 1GB. The VM has no GPU and hence has no use for lots of VRAM. Make sure the VRAM setting is comfortably above the level at which the settings dialog gives a warning, that's all.