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Re: JFFS compression and hard links.




jadb@xxxxxxx.com said:
>  This I like... so would this mean that at mount time we would only
> have  to read the sectors containing dir entries? 

Strictly speaking, yes. But all sectors may contain dir entries, so we 
still have to scan them all :)

> It sure takes a while to  scan the flash now. 

Checkpointing will remove the need to scan the whole flash. But even with 
separate dirents, you'll have to scan the whole flash to make sure you've 
found them all before you can do anything useful.

You're still running without sjhill's fix to cache the initial scan, which 
speeds things up by a few orders of magnitude.

For now, I'm not going to get involved in the checkpointing. It may be useful 
at this stage to define the first few bytes of a checkpoint node as

 __u32 magic
 __u32 nodetype /* Or whatever magic/nodetype setup we decide on */
 __u16 length

... so the current code can at least know how to skip over it, so that 
it'll be able to read filesystems created later on when we've implemented 
checkpointing.

Is 64KiB large enough for the checkpoint node?

--
dwmw2



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