[Yaffs] Why do I get a "gc prioritised or allocator out" mes…

Fill in the YAFFS partition untill 99% used,
then unmounting partition,
after printing messages :

yaffs block 1 gc prioritised
yaffs block 2 gc prioritised
yaffs block 3 gc prioritised
yaffs block 4 gc prioritised
yaffs block 5 gc prioritised
yaffs block 6 gc prioritised
yaffs block 7 gc prioritised
yaffs block 8 gc prioritised
yaffs block 9 gc prioritised
...

Fill in the root partition untill 99% used,
then restart system,
leaving the system unable to start normally any more and print messages:

!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!
yaffs tragedy: no more eraased blocks
!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!
yaffs tragedy: no more eraased blocks
!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!
yaffs tragedy: no more eraased blocks
!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!
yaffs tragedy: no more eraased blocks
!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!
yaffs tragedy: no more eraased blocks
!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!
yaffs tragedy: no more eraased blocks
!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!
yaffs tragedy: no more eraased blocks
...

Software and hardware environment :
linux kernel 2.6.19.2 ,
nand flash samsung k9f1208,
Freescale MX27 ARM926EJS.

Why do I get a "gc prioritised or allocator out" message?

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2008-11-06
Bentley Song
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