Slow mount of JFFS2 root file system

[Lin, Bin (Bin)]

Hi,

I was able to trace down to the location in the code that causes slow root files system mount. When the code scans through medium, most of unused area in the flash (30M of 60M bytes) is scanned as obsolete nodes:

                if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
                        /* Wheee. This is an obsoleted node */
                        D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
                        DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
                        ofs += PAD(je32_to_cpu(node->totlen));
                        continue;
                } 

It takes very long time to scan through all the obsolete 128 byte nodes.
The question is what causes the unused sectors being marked as obsolete? 

Thanks a lot for your reply.
Ben

-----Original Message-----
From: linux-mtd-bounces at lists.infradead.org [mailto:linux-mtd-bounces at lists.infradead.org] On Behalf Of J?rn Engel
Sent: Tuesday, January 15, 2008 10:49 AM
To: Lin, Bin (Bin)
Cc: linux-mtd at lists.infradead.org
Subject: Re: Slow mount of JFFS2 root file system

On Tue, 15 January 2008 09:22:04 -0500, Lin, Bin (Bin) wrote:
> 
> I have ARM9 systems with JFFS2 root file system. For some reasons, e.g.
> system crash or power failure, when system boots up next time, it 
> takes much longer time than usual to mount jffs2 root file system. It 
> can hang at following message for 3-10 min. Once this happens, the 
> mount will take the same long time in every reboot later on. Even 
> though it take long time to mount root file system, the system can 
> still come up and function well. This problem occurred in less than 
> 10% of boards in the field, but can not be reproduced in the lab. I 
> have been struggling with this is issue for weeks.

What stops you from retrieving one such board from the field?  Should be easy to debug once you have it on your desk.

Jörn

--
Prosperity makes friends, adversity tries them.
-- Publilius Syrus

______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/