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From: Sergei Sharonov <sergei.sharonov@halliburton.com>
Subject: Re: UBI Used In Commercial Products ??
Date: Wed, 31 Oct 2007 23:01:07 +0000 (UTC)
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Hi,
> JFFS2 has been modified to sit on top of UBI.

Yes, I know. Is that better then JFFS2 on top of mtdblock device?
  
> One thought here is that I would think that mounting is a fairly rare
> occurance.  
> You're much more likely to coming back from suspend.  Notice the
> difference in time it takes from my HP iPAQ to power-on normally vs a
> cold boot.  It is very different. 

Still one must plan for the worst case and the worst case for me
was about 2 hours of mount time after I used ftp to transfer large file.
I suspect ftp was writing really small jffs2 nodes.
Disclaimer: that was about 2 years ago and jffs2 might have improved,
processor (ARM9) was not a speed demon either.
If you do that on your iPAQ (create large file with lots of small nodes)
and then cold boot it - would you be willing to wait for an hour for it to 
become usable again?

I really hope UBI+UBIFS will overcome this problem. Still there is a concern 
here since UBI scales linearly. Can somebody plz post UBI scan time for large
flash array?

Regards,

Sergei Sharonov