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>> need of rewrite few full tracks worth of data, but otherwise will
>> then be compatible and can i use it as usual?
>
> My understanding is that the SMR drives are actually different class
> of storage device.
>
> The "drive managed" drives as shipped now tries to emulate normal hard
> drive's behavior but they present unique risks: for instance, a
> rewrite of a small block may end up in a read-modify-write of a much
> larger area, so we must refrain from doing such operations for

small part (like 10GB) of storage space is formatted without SMR and used 
as log. writes that doesn't fit full SMR stripe are first written to log 
then (after possibly very long delay and some coalescing) - 
read/modify/writted to normal space