[geeks] Flash drive questions

[Lionel Peterson]

>From: Charles Shannon Hendrix <shannon at widomaker.com>
>Date: 2006/08/06 Sun PM 10:43:14 CDT
>To: The Geeks List <geeks at sunhelp.org>
>Subject: Re: [geeks] Flash drive questions

>Sun, 06 Aug 2006 @ 19:57 -0500, Lionel Peterson said:
>
>> The idea is not to use the flash drive for scratch pad/temporary
>> files, but nearly static files that take up a lot of space and are
>> used infrequently (relatively speaking - like DLL files)...
>
>OK, but what is the point?
>
>A good OS already does this for you, from RAM that is way faster than
>flash.

Well, again, I'm playing devil's advocate - I am not saying this is the way to go, I asked if anyone knew about these "technologies".

In my mind, the executables (DLLs, etc.) would remain in flash memory and not have to be reloaded each time the unit is powered up...

Also, no one ever said flash was faster than RAM, but if you off-load executables to flash, that frees up more of that faster RAM for other uses.

Yes, SCSI is faster than flash, but very few comodity PCs (the target for Vista O/S) have SCSI subsystems - SATA is very popular, but is far from the majority of systems in the field (opinion, not fact) and approaches the speed of SCSI. If the platform has a maximum RAM capacity of, say, 512 Meg due to hardware design, using a flash device to augment the available (faster) RAM is a possible application. And ROMs are slower than RAM as well - it was (and may still be) common for PCs (you know, x86-thingies) to copy the BASIC (and other) ROMs into RAM for faster execution...

I agree, this makes little sense in a desktop with gobs of gigabytes of RAM or a lightning-fast SCSI subsystem, but in a power-sensitive application (where battery life can trump procesor speed) this could have uses. COULD.

Finally, I was under the impression that flash devices (say, a CF card) has a small bit of logic inside that scatters the writes around the device, and it manages collection of dead "sectors" (for lack of a better term) to avoid problems. To detect a problem with a flash device, you just need to keep track of the availble space on the device - as it declines, "sectors" are failing and the device should be replaced. That it is not tracked/managed currently doesn't mean it couldn't be...
 
Lionel