Flash disks and FFS layout heuristics

[Poul-Henning Kamp]

In message <20080331222154.C976C5B50 at mail.bitblocks.com>, Bakul Shah writes:
>On Mon, 31 Mar 2008 13:06:10 PDT Matthew Dillon <dillon at apollo.backplane.com>  wrote:
>>     But how do you index that information?  You can't simply append the
>>     information to the NAND unless you also have a way to access it.  So
>>     does the filesystem have to scan the NAND (or significant portions of it)
>>     in order to build an index of the filesystem topology in system memory?
>
>One possible way:
>
>I'd design the system so that each update ends with the write
>of a root block[1]. 

This is sort of the approach Margo Seltzer used for her (Kludge-)LFS
it has many drawbacks, in particular when it comes to recovery.

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