General performance of NAND operations i.e mount and ls

Artem Bityutskiy dedekind at
Thu Sep 6 07:11:59 EDT 2007

On Thu, 2007-09-06 at 12:11 +0300, Artem Bityutskiy wrote:

> > Okay, I wanted to check if the time is okay for 520MHz core with 104MHz
> > Bus and 8Bit flash. If this is the case my Hardware driver is okay.
> > There is no urge to improve this stat() time and fragtree building at
> > the moment. If it takes so long and the driver is okay it wioll take so
> > long (arguing with boss and customers :-)).
> Try to measure raw R/W, e.g with dd. But beware dd will fail at the
> first met bad block. Something like:
> Read: dd if=/dev/mtd4 of=/dev/null bs=4096 count=512
> Write: dd if=/dev/zero of=/dev/mtd4 bs=4096 count=512
> It'll print raw R/W speed.  But beware dd will fail at the first bad
> block, so yo may have to play with count= or skip= for read and seek=
> for write to find a large enough contiguous area without bad blocks.


may you please go to Device Drivers--->Memory Technology Device (MTD)
support--->UBI - Unsorted block images---> in menuconfig and enable "UBI
debugging", "UBI debugging messages", and "Extra self-checks" and try
again? Then send what UBI prints. I'll try to figure out what is wrong.

Best regards,
Artem Bityutskiy (Битюцкий Артём)

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