Filesystem on CF with EWF

  • Thread starter Thread starter Thomas Johansen
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Thomas Johansen

Hi

I just whant to get some feedback on whisch filesytem you think is best to
use on my CF card with EWF.

The CF card has 2 partition. The first for the WinXPe and its protected and
the second is for user data storage and is not protected.

I been thinking of using NTFS on both partitions, where the last access time
stamps is disabled, for best performance

Any down side of using NTFS instead of FAT ??

What are you thinking is the best ?

/Rhomas
 
Thomas,

Opinions on this are divided so I won't influence you by mine, only what I
can tell you is where to look.

1. Check EWF memory overlay usage after same time on your full XPe system
with FAT then with NTFS. Compare what is greater.
2. Check number of writes done by each FS to partition or to disk in whole.
(EWF disabled)
3. Check number of writes done to each sector separately on boot partition
and on non boot partition. (EWF Disabled, but you won't be able to do this
test :-( )

Regards,
Slobodan
 
Thanks.. I'll try out some test, when I got it all up running.

I'm actually more interested in stability then RAM usage and speed.
So it doesn't matter a great deal if the RAM overlay is a bit higher. when
used with a diffrent FS.
In my own book, NTFS is much better then FAT, specilly when stability is in
mind.

Ware leveling is allso a big issue to take in mind, when running with CF.
But if the partition is protected by EWF, i guees the number of writes is
kept at a minimum. Of course our application will commit some of the changes
to the EWF protected driver, when we are doing som eupgrad of the system,
but that schouldn't be much ( Just normal bug fixes :-) )

/Thomas
 
Thomas,
Thanks.. I'll try out some test, when I got it all up running.

I'm actually more interested in stability then RAM usage and speed.
So it doesn't matter a great deal if the RAM overlay is a bit higher. when
used with a diffrent FS.
In my own book, NTFS is much better then FAT, specilly when stability is in
mind.
Click to expand...

It is, no doubt but on unprotected partition only, right? On protected partition you don't gain much using NTFS as all writes go to
overlay anyway.
Ware leveling is allso a big issue to take in mind, when running with CF.
But if the partition is protected by EWF, i guees the number of writes is
kept at a minimum. Of course our application will commit some of the changes
to the EWF protected driver, when we are doing som eupgrad of the system,
but that schouldn't be much ( Just normal bug fixes :-) )
Click to expand...


You said it yourslef. For stability you would want to keep the number of writes at minimum. With NTFS it is less flexible as the FS
is chattier and less documented than FAT.
FAT on EWF protected volume has an advantage of being more simple and therefore more predictable than NTFS. I mean it will be easier
and mo consistent to estimate the EWF overlay (RAM/DISK) usage with FAT.

In any case, regardless of FS used, lower the EWF usage as much as possible:
http://msdn.microsoft.com/embedded/community/community/tips/xp/ramewf/default.aspx

Btw, for NTFS there are more flags that should be turned off on EWF protected volume. E.g., auto growth for MFT, etc. (check out
fsutil utility related switches)
 
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