On Thursday 19 August 2010 13:15:32 levin wrote:
> hi all,
>   By the speed comparison on the site,  I changed some configuration in
> yaffs2/yaffs2_guts.h to
> #define YAFFS_BYTES_PER_SPARE        64
> #define YAFFS_BYTES_PER_CHUNK        2048
> #define YAFFS_CHUNK_SIZE_SHIFT         11
> #define YAFFS_CHUNKS_PER_BLOCK     64
>
> originally it's
> #define YAFFS_BYTES_PER_SPARE        16
> #define YAFFS_BYTES_PER_CHUNK        512
> #define YAFFS_CHUNK_SIZE_SHIFT         9
> #define YAFFS_CHUNKS_PER_BLOCK     32

The above only apply to the yaffs1 mode which does not apply to you.

> besides the nand flash i used is 16bits wide-bus and support 2kB
> page(chunk) read.
>
> but there is no read and write speedup.
> Whether  there are some other changes needed to fit it.
> The operating system is linux 2.6

You need to make the appropriate changes in the Linux mtd layer so that it 
provides the correct information to yaffs.