Re: [Qemu-devel] What is the minimal linux setup for running Qemu ?

[Jim C. Brown]

On Thu, Dec 23, 2004 at 01:40:57AM +0000, Richard Neill wrote:
> 
> 
> What *would* be cute would be to use the virtual vfat driver. Thus files
> on the guest map to real files on the memory key. If you do this, the
> number of writes will be exactly the same as if you used the memory key
> for transport of files in the usual way.
> 
> 

Or you could use a loopback on a RAM disk, and then merely copy the loopback
to the flash when you are done. This actually reduces the writes (since you then
only need to write one file out per session) but has its cost in reliability
(if something happens and the session ends w/o the loopback being copied over
(say power goes out) then you loose all the work you have done for that 
session).

> 
> The only problems that remain are:
>       -  vfat doesn't support Linux file attributes.
>             (there is a solution, but I forget what).

There are 2 that I know of, but they both have costs:

Simplest is to use a loopback file system on the vfat. This would be quite
badly inefficent tho, and may incur a significant cost in extra writes.

The other solution is to use either umsdos or uvfat. These require an extra
"hidden" file per directory, and the file gets written every time you update
unix file attributes and such, so this incurs an addition cost.

> 
>       - you need a script to manually save those files within /home
>           that you want to keep. Most can vanish with the ramdisk on
>          reboot, but things like ~/.ssh  and ~/.mozilla are useful!
>       [DSL and Knoppix both solve this problem somehow ]

I think, by coping those files manually to a directory on the DOS partition of
the hdd.

-- 
Infinite complexity begets infinite beauty.
Infinite precision begets infinite perfection.