Re: Booting from flash and EWF

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

Instead of EWF, take a look at FBWF (http://www.seanliming.com/Docs/FBWF.pdf). You can open holes for log files.

Although flash technologies is getting better, you still want to protect from sudden power downs and protect flash life with one of the Write Filters.

Regards,

Sean Liming
www.sjjmicro.com / www.seanliming.com
Book Author - XP Embedded Advanced, XP Embedded Supplemental Toolkit

"Sasa" <sasa555@xxxxxxxxx> wrote in message news:fcth3r$sch$1@xxxxxxxxxxxxxxxxx
Hello everybody,

I am working on a kiosk application and considering using only usb flash as a boot disk. This is very convenient because it makes disk switching on the deployed kiosk veary easy - the technical person must simply open the kiosk, pull the current usb stick and insert new one.

From what I saw (and also been advised here couple of months ago) - in such cases it is advised to use EWF in order to protect the media from excessive writes. My application doesn't write much - it does some logging here and there but that's basically all it writes. However, I suppose the OS itself does occasional writing. I am therefore considering using RAM disk overlay.

With this in mind, my questions would be:
1) Do I really need EWF if OS is virtually the only significant writer.

2) How much extra RAM would I need due to EWF? My estimation is that I should get by with the flash of 1 GB, where the disk usage after FBA is finished is aprox. 600 MB, the remaining space is needed exclusively for the log, and anything OS needs to persist (page file and such). Does this means I should use extra 1 GB of RAM for overlay?

3) If I understand correctly - the data is persisted only on shutdown / reboot of the system. However I want my log data to be persisted immediately (without the need for the subsequent reset of the system). This is basically stored in one file where I append log entries. All other writes should be persisted as rarely as possible (in order to protect the media from the excessive writes). Can this be implemented and if so - how?

Thanks in advance!

Best regards,
Sasa



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