[Yaffs] Yaffs2 slowdown issue.

[Charles Manning]

On Friday 13 January 2006 12:04, Clemens.Doug wrote:
> I am using YAFFS2 on a 1 Gig NAND flash and am experiencing a slowdown
> every time I mount the flash. This mostly occurs when I have deleted a
> lot of files on the flash. It takes more than the 60 second timeout to
> complete the mount in some cases.
>
>
>
> I tracked the slowdown to the yaffs_ScanBackwards function.

Yes, this is what does all the scanning at mount time.

Scanning deleted files is only marginally faster than scanning existing files. 

One thing that would help would be running some sort of "extra clean" garbage 
collection that removes all the deleted garbage, thus making future mounts 
etc much faster.

>
>
>
> Is this just "normal operation" for this size of flash? If so is there a
> way to clean up memory to speed this up?

This is actually pretty good for a log structured fs. 

There are some things that would help to speed things up that I would like to 
try doing in the next few months.  These have been discussed briefly a few 
times before.

-- CHarles