mtd caching in kernel 2.6

mtd caching in kernel 2.6

[Hyphen79]

Hello,

I have a problem with my mtdblock root device with the 2.6 kernel. When 
I write data to a mtd partition,
which is not the root, the data will be written immediately. But when I 
write something to the root partition,
it will be cached and written to it after a while (~30sec). What could 
this be and how could I deactivate
the caching? - the root is a cramdisk, not JFFS2 - and I have no 
problems with the 2.4 kernel.

Many thanks ahead!

Re: mtd caching in kernel 2.6

[Nancy]

On 6/11/08, Hyphen79 <hyphen79@web.de> wrote:
> Hello,
>
> I have a problem with my mtdblock root device with the 2.6 kernel. When
> I write data to a mtd partition,
> which is not the root, the data will be written immediately. But when I
> write something to the root partition,
> it will be cached and written to it after a while (~30sec).
Yes, cause your root is cramdisk, goes to block device layer
mtdblock.c Which is cache designed. Your other partitions works with
JFFS2 or Yaffs2 which goes directly on MTD nand_base.c or similar
file.

What could
> this be and how could I deactivate
> the caching? - the root is a cramdisk, not JFFS2 - and I have no
> problems with the 2.4 kernel.
No, you can't deactiveate the caching. But you can avoid it by using
JFFS2 or YAFFS2 as your rootfs. I think your case have nothing to do
with the kernel version. It should be the same with 2.4 kernel.

-- 
Best wishes,
Nancy