Re: [9fans] disk/^(mbr format fdisk prep)

[Charles Forsyth <forsyth@terzarima.net>]

>>How would one go about adding a "user mode wear-leveller" atop kfs, for
>>example? general outline is okay.

i'm not sure it is.  it needs to take account of physical not logical
location, because it's the wear on the physical location that matters,
and perhaps the topology-- for instance, depending on the flash and
algorithm it might be necessary to move the same block content from
one physical block to another without changing the logical address--or
on some flash move every block within a flash segment at least once
every 10,000 writes-- and if `such things should just appear as raw
disks' the physical location won't be visible to the higher level file
system without an interface peculiar to flash.

that's why the usual approach to providing a `raw disk' on top of flash
sits below the file system, not above it.  it's still not as efficient as a storage system
designed for flash.