Hi, On Tue, 6 Oct 2020 at 13:40, siha lawrence <sihaj33@xxxxxxxxx> wrote: > > Hi, > > What parameters could we use to write/read OD, MD, ID of a disk or > specific LBAs? > > Thanks, > Siha It seems like OD (Outer Disk), MD (Middle Disk) and ID (Inner Disk) are SMR drive terms. I don't know how you explicitly target those... maybe someone more familiar with SMR would know? (I've CC'd Dmitry in case they know). If you want to write a specific LBA you will have to get as close to the disk as possible. If we're talking Linux you can access the disk's raw block device (filename=/dev/<dev>), use direct=1, set blocksize to the underlying block size and then you could play back a hand crafted iolog (https://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-arg-read-iolog / https://fio.readthedocs.io/en/latest/fio_doc.html#trace-file-format-v2 ) where the offset would correspond to the LBA. -- Sitsofe | http://sucs.org/~sits/
