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Why does U3 copy local?

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FeeserAndrew
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Why does U3 copy local?

I've been looking at the U3 technology and I noticed that the launchpad copies the application to the C:\ drive first, then runs it from there.

Is there a real benefit to this? I mean, isn't the app loaded into memory anyway? Is there a functional benefit to running the app locally vs from the portable drive directly?

Thanks,
Andrew

Aciago
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speed?

Just guessing... I really don't know...

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I have no signature again... Cry

If a packet hits a pocket on a socket on a port,
and the bus is interrupted as a very last resort,
and the address of the memory makes your floppy disk abort,
then the socket packet pocket has an error to report Biggrin

Bensawsome
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If they wanted speed then

If they wanted speed then they wouldn't copy it 2 the local drive because then it takes time 2 copy and if u have a crappy write speed then it could take a bit.
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alanbcohen
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Just an idea...since solid

Just an idea...since solid state technology on today's usb drives has an inherent limit on the number of writes you can perform, there will be an extension of life in apps that write back to themselves if you first copy them to magnetic media, use them there, and then copy back to the usb drive at the end. You will write every byte, but each will be written only once.

RMB Fixed
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One reason :

U3 drives have a "safely eject" function to avoid data-corruption.
If the launchpad was running from the flash-drive that wouldn't
work because the drive would be in use .

Since the U3-launchpad resides on the read-only CD-"partition"
it is not to prolong the life of the drive.

Liberta Autostart does the same, spawns a copy of itself to a
temp-location on the host .
In fact : Scr*w the U3-Launchpad, Liberta works great
from the U3-CD-device and is tiny, leaving you with plenty space to
hold truecrypt... that it also supports ..

FeeserAndrew
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hmm

Well, that would make sense I guess, but doesn't the data portion still reside on the portable drive? Is there really a high risk of data corruption by running apps from the portable? Anyone know if the PortableApps suite copies the files locally?

- Andrew

Simeon
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Well...

AFAIK:
- Yes the data partition is still on the usb drive.
- I dont think so
- No, the PortableAppsMenu doesnt copy files to your local Ccomputer. Thats one of the reasons you cant safe eject the drive like you can U3 drives. But I think John is working on something...
“Science is the belief in the ignorance of the experts” - Richard P. Feynman

"What about Love?" - "Overrated. Biochemically no different than eating large quantities of chocolate." - Al Pacino in The Devils Advocate

John T. Haller
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Wrong

Ok, let's get this all straight. U3 has the ability to leave application files (binaries) within a zip file and extract them to the local PC to run them. But, a good chunk of apps don't do this because it is slow to start up and you have to trust that the local PC will have enough space and a faster drive.

The data is always stored on the portable drive. Which is why you should NEVER unsafely eject, since it will corrupt your data if it happens to be writing to a file at that particular moment. U3's demos where they show people yanking the drive out are simply irresponsible as U3 has no mechanism at all to minimize data corruption of settings, etc.

Sometimes, the impossible can become possible, if you're awesome!

RMB Fixed
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Yes,the data resides on the

Yes,the data resides on the portable drive, including any changes
you have made to the U3 LaunchPad-menu.
No, there isn't a higher risk of data-corruption just by
running apps from the portable drive, the risk is introduced
when you remove the drive by just pulling it out while you have
files on it open, especially if you have activated caching of the drive.
The "safely eject" function checks that all writes have been done and that
there are no open files (including programs) on the drive .
On U3 drives it is also supposed to clean up the Host by deleting the
temp-folder that the Launchpad was spawned to.
This doesn't happen if you just " pull the plug " ..

Simeon
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but

the U3 always leaves a folder with a file in it on the host machine.
“Science is the belief in the ignorance of the experts” - Richard P. Feynman

"What about Love?" - "Overrated. Biochemically no different than eating large quantities of chocolate." - Al Pacino in The Devils Advocate

FeeserAndrew
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maybe not

I don't think yanking the drive should stop the launchpad from cleaning up, because the launchpad is running from memory technically and can detect that the drive has disappeared.

So stop me if I'm wrong....but what we have concluded is that there's no real benefit to copying the app locally before executing, and doing so actually slows down the load time.

BTW.....Simeon, I love your quote hehe.

Simeon
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Thanks ;-)

Maybe I should change it.
I had that one for quite some time.
"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong." - Richard P. Feynman

"What about Love?" - "Overrated. Biochemically no different than eating large quantities of chocolate." - Al Pacino in The Devils Advocate

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