Bad Blocks...

[Eddie Dawydiuk]

Hello Yaffers,

After running some stress tests on a 128MB NAND Flash I have found some
strange behavior while using the Yaffs filesystem... The stress test
creates a ring-buffer of 5 directories, each directory contains 10,000
files with a size of 1248 bytes (Please find the source code attached). 
When running this application on a 32MB NAND Flash I am able to fill the
disk and then delete the files as expected... Although when running the
test on a 128MB NAND Flash(with the same kernel) I find that after
creating slightly over 35,000 files I am unable to write any more files to
disk(my board hangs). After rebooting the board, when I attempt to delete
the files only some of the files are deleted successfully(on the first
attempt). After attempting several more times I am able to delete all of
the files but I find that I have hundreds of bad blocks(there are no error
messages when I attempt to delete a file and it is unsucessfully deleted).
I have provided the output of /proc/yaffs below(after running the stress
test multiple times) and am using a 2.4.26 kernel... I have read the other
posts refering to bad block management
(http://www.aleph1.co.uk/pipermail/yaffs/2005q1/000955.html) and have
ensured the fixes suggested have been made. If anyone has any suggestions
I would appreciate them...

$ cat /proc/yaffs
YAFFS built:Apr 26 2005 10:44:45
$Id: yaffs_fs.c,v 1.3 2005/01/25 00:38:25 eddie Exp $
$Id: yaffs_guts.c,v 1.41 2005/04/24 08:54:36 charles Exp $

Device yaffs
startBlock......... 1
endBlock........... 7999
chunkGroupBits..... 2
chunkGroupSize..... 4
nErasedBlocks...... 1575
nTnodesCreated..... 35000
nFreeTnodes........ 21790
nObjectsCreated.... 34400
nFreeObjects....... 21795
nFreeChunks........ 142801
nPageWrites........ 71420
nPageReads......... 2573700
nBlockErasures..... 4021
nGCCopies.......... 317
garbageCollections. 3599
passiveGCs......... 3599
nRetriedWrites..... 0
nRetireBlocks...... 2397
eccFixed........... 0
eccUnfixed......... 0
tagsEccFixed....... 0
tagsEccUnfixed..... 654
cacheHits.......... 0
nDeletedFiles...... 22161
nUnlinkedFiles..... 22162
nBackgroudDeletions 0
useNANDECC......... 1

Thanks,
Eddie