Lorewegian 📚 on Nostr: it's a dick move on the part of HDD manufacturers to sell SMR drives without writing ...

it's a dick move on the part of HDD manufacturers to sell SMR drives without writing in big fat bold letters on them that they're the trashy option.

so

normal hard drives are now known as CMR (Conventional Magnetic Recording) drives. they had to retrospectively invent a name for them, now that there's a worse option in town.

these new ones are SMR (Shingled Magnetic Recording).

so, on a normal hard drive, data is stored a bit like on a vinyl record, on parallel tracks.

what SMR does is actually to put these tracks a little bit too close together. normally, this would ruin the data on the next track over, but the way they fix it is to compensate. turns out you can pack them closer together if you make sure to counteract the magnetic flux in JUST the right way.

but you HAVE to write out several tracks as a group to do this. and this group is called a zone.

unlike regular drives, where you can write out a single sector of 4 kB, on these drives, you're looking at writing out 256 MB or more if you're only changing a single sector of data.

if you're writing out big files, this is fine, but performance for small random writes is going to be horrible. the technique relies heavily on caching and writing out later to work properly.

so they're not very good, *especially* not for things like NAS or DB servers, where you *really* want stuff to be written to disk immediately for the sake of data integrity.