XPe on Compact Flash

[Peter Herijgers]

Does Windows XP embedded uses some kind of a swap/page file?
I the answer is yes what about the livetime of the CF?
I believe the CF cannot be written more than 100.000 times.

Peter.

 

[KM]

Peter,

Yes, you can turn on pagefile support in your XPe image. Look at the settings of HAL (" ... PC") component in your image
Configuration.

To prolong CF lifespan you can add and set up EWF (enhanced Write Filter) to your XPe image.
Read more here: http://msdn.microsoft.com/library/en-us/xpehelp/html/xetbsCompactFlash.asp

 

[Slobodan Brcin \(eMVP\)]

Hi Peter,

Just to add to that:
You can enable pagefile but it is not recommended to do so on CF. Unless you need some performance counters functions to work.

Best regards,
Slobodan

 

[KM]

Agree.

Although we still don't know for sure how EWF and Pagefile live together.

 

[Slobodan Brcin \(eMVP\)]

Although we still don't know for sure how EWF and Pagefile live together.

This still stand on my to-test list when I get some time or at least one HDD partition to do FBA.
I don't want even to try using page-file on XPe booted from USB. As I understood USB driver stack is not designed to support this.

Best regards,
Slobodan

 

[Jon Fincher [MS]]

This still stand on my to-test list when I get some time or at least
one HDD partition to do FBA. I don't want even to try using page-file
on XPe booted from USB. As I understood USB driver stack is not
designed to support this.

Don't bother, Slobodan - it's a waste to have a pagefile on an EWF
system. Think about it - EWF uses RAM to simulate disk space, while a
pagefile uses disk space to simulate RAM. Using both means you're using
RAM to simulate disk space that's being used to simulate RAM. Ever see
Victor/Victoria?

Look at it another way - every new write to the pagefile incurs more EWF
RAM memory, meaning you'll have less RAM for your programs and therefore
need more pagefile, which means less RAM for your program and more
pagefile, ad nauseum. You could set the pagefile size to be static, but
it will still consume EWF RAM space.

 

[KM]

Jon,

Don't bother, Slobodan - it's a waste to have a pagefile on an EWF
system. Think about it - EWF uses RAM to simulate disk space, while a
pagefile uses disk space to simulate RAM. Using both means you're using
RAM to simulate disk space that's being used to simulate RAM. Ever see
Victor/Victoria?

I think this was more an interesting issue to investigate rather than a real usage.

Look at it another way - every new write to the pagefile incurs more EWF
RAM memory, meaning you'll have less RAM for your programs and therefore
need more pagefile, which means less RAM for your program and more
pagefile, ad nauseum. You could set the pagefile size to be static, but
it will still consume EWF RAM space.

My testing results were (don't know Slobodan's results yet) that dispite the fact that pagefile was created and used via EWF (when
reboot without commit the pagefile disappeared), the EWF used was not growing as much as I consumed pages from the paged pool. Yet
the EWF memory usage was small (tested with minlogon image). That fact confused me.
I think I have sent the test results to Slobodan and Troy.

Konstantin

 

[Slobodan Brcin \(eMVP\)]

Hi Jon,

I think this was more an interesting issue to investigate rather than a real usage.

Exactly, curiosity only

My testing results were (don't know Slobodan's results yet) that dispite the fact that pagefile was created and used via EWF (when
reboot without commit the pagefile disappeared), the EWF used was not growing as much as I consumed pages from the paged pool. Yet
the EWF memory usage was small (tested with minlogon image). That fact confused me.
I think I have sent the test results to Slobodan and Troy.

According to this test (I have not repro it yet). Small increase in EWF overlay is created because when pagefile is created and as
it grow FAT table changes and thus RAM overlay usage increase.
But data that should go to physical disk never get there, also they never get to RAM overlay either.
So they are lost somewhere. And this is intriguing behavior.

Best regards,
Slobodan

 

[Peter Herijgers]

If I run the TPA on my Target system and include the EWF in my Tagret
Designer I am OK?
And of course following the rules about EWF.

RAM is not a problem because the are cheap and I don't need a high
performance system.
Just a touchscreen with some network capabilities.

So pagefile and swapfile (maybe they are the same, I don't know) is by
default not in my Image, just running TPA?

Peter.

 

[KM]

Peter,

If I run the TPA on my Target system and include the EWF in my Tagret
Designer I am OK?

You also have to set up EWF component settings in TD.

If you go with Slobodan's RAM EWF component, you better read the component
release notes.

And of course following the rules about EWF.

RAM is not a problem because the are cheap and I don't need a high
performance system.
Just a touchscreen with some network capabilities.

So pagefile and swapfile (maybe they are the same, I don't know) is by
default not in my Image, just running TPA?

swapfile is a just an old name (coming from Windows 3.0 and earlier times)
for the pagefile.

You have to go to your configuration HAL ("... PC") component settings in TD
to enable the pagefile support.