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Kai Krakow posted on Mon, 15 May 2017 21:12:06 +0200 as excerpted:

> Am Mon, 15 May 2017 14:09:20 +0100
> schrieb Tomasz Kusmierz <tom.kusmierz@gmail.com>:
>> 
>> Not true. When HDD uses 10% (10% is just for easy example) of space
>> as spare than aligment on disk is (US - used sector, SS - spare
>> sector, BS - bad sector)
>> 
>> US US US US US US US US US SS
>> US US US US US US US US US SS
>> US US US US US US US US US SS
>> US US US US US US US US US SS
>> US US US US US US US US US SS
>> US US US US US US US US US SS
>> US US US US US US US US US SS
>> 
>> if failure occurs - drive actually shifts sectors up:
>> 
>> US US US US US US US US US SS
>> US US US BS BS BS US US US US
>> US US US US US US US US US US
>> US US US US US US US US US US
>> US US US US US US US US US SS
>> US US US BS US US US US US US
>> US US US US US US US US US SS
>> US US US US US US US US US SS
> 
> This makes sense... Reserve area somehow implies it is continuous and
> as such located at one far end of the platter. But your image totally
> makes sense.

Thanks Tomasz.  It makes a lot of sense indeed, and had I thought about
it I think I already "knew" it, but I simply hadn't stopped to think about
it that hard, so you disabused me of the vague idea of spares all at one
end of the disk, too. =:^)

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman