Friday, April 17th 2020
Seagate Guilty of Undisclosed SMR on Certain Internal Hard Drive Models, Too: Report
Earlier this week, Western Digital was in the line of fire when it emerged that several of its WD Red family of "NAS-optimized" hard drives allegedly employ some form of shingled magnetic recording (SMR), a physical-layer data writing technique that maximizes density at a heavy cost of random write performance that effectively makes the HDDs unfit for use in RAID volumes, and in turn most NAS applications that commonly employ RAID and encourage end-users to build RAID volumes for data redundancy. A new report by Blocks & Files finds that the issue is more widespread than previously thought, and that even Seagate employs it without disclosure on certain models.
Several of Seagate's higher capacity Barracuda desktop internal hard drives use SMR without disclosing it in their data-sheets. These include the 8 TB ST8000DM004, and 5 TB ST5000DM000. Both these drives are sold under the Barracuda Compute brand, which markets "home servers, entry-level DAS, and desktop computers" among its use-cases. Seagate does market its Archive and Exos lines of HDDs are employing SMR, but mention of the technique is buried in their data-sheets, and not prominently in product marketing or packaging. Archive and Exos are targeted at bulk cold storage setups where capacity is more important than performance. Meanwhile, Toshiba has confirmed that its Desktop HDDs too employ SMR. The company's MQ04 2.5-inch and DT02 3.5-inch HDDs employ "managed SMR" (i.e. use conventional recording and switch to SMR as the platters are running out of space).
Source:
Blocks & Files
Several of Seagate's higher capacity Barracuda desktop internal hard drives use SMR without disclosing it in their data-sheets. These include the 8 TB ST8000DM004, and 5 TB ST5000DM000. Both these drives are sold under the Barracuda Compute brand, which markets "home servers, entry-level DAS, and desktop computers" among its use-cases. Seagate does market its Archive and Exos lines of HDDs are employing SMR, but mention of the technique is buried in their data-sheets, and not prominently in product marketing or packaging. Archive and Exos are targeted at bulk cold storage setups where capacity is more important than performance. Meanwhile, Toshiba has confirmed that its Desktop HDDs too employ SMR. The company's MQ04 2.5-inch and DT02 3.5-inch HDDs employ "managed SMR" (i.e. use conventional recording and switch to SMR as the platters are running out of space).
19 Comments on Seagate Guilty of Undisclosed SMR on Certain Internal Hard Drive Models, Too: Report
I wonder why it only is said now...
Yes, I know a lot of people install games and programs to HDDs and run those off of the HDD. And really, SMR drives work just fine for that. They all have a small part of the drive that is used as a traditional CMR drive to absorb small writes(kind of like a pseudo-SLC cache in an SSD). And even when that cache is full, the write speed is still fast enough to keep up with an internet connection if you are downloading a large game off Steam or something like that. And read speeds on these drives are normal just like any other HDD, it's only the writes that are slow. I've been using one as my programs/games drive in my AMD rig for years, and there was really only one time when I noticed slowness and that was when I was installing Adobe Suite from an external SSD. It took about double the time it normally takes to install to a hard drive.
On the other hand WD use SMR drives and labelled them for RAID/NAS use. This is a big no-no without actually telling the customer the drives are SMR. Using SMR drives in a RAID is fine if all the drives are SMR. But micing SMR and CMR drives can lead to problems. You need either all CMR or all SMR drives. Without proper labeling by WD, this becomes a nightmare.Not really, it should be pretty easy to do actually. With SMR, the write head is bigger than the tracks, lets assume it's 3 tracks wide. So when you write something to the drive, you have to write multiple tracks at once. This slows down write dramatically, because if you only need to write data to 1 of the tracks, you first have to read the data from the other 2 tracks, write the data from the other 2 tracks somewhere else temporarily(you can't store it in volatile RAM because it would risk data loss in a power failure), then write the data for all 3 tracks. So, say the write head is 3 tracks wide and it is a 6TB drive. The first 2TB is written by just writing one of the 3 tracks, the other 2 overlapping tracks aren't written. Once 2TB of the drive is use, the single tracks are full, it starts using SMR to write to the other overlapping tracks.
maybe not every brand does this, but I think its still safe to assume that
business.kioxia.com/en-us/ssd/client-ssd/bg4.html
I know their early perpindicular recording drives had issues, but that was nearly a decade ago, now.
www.seagate.com/enterprise-storage/exos-drives/exos-e-drives/
Exos 5E8 (Formerly Archive HDD v3)
Perfect for Archival dataI believe that is the only Exos (enterprise) product that uses SMR. They can be RAID'd for redundancy but don't expect them to random write very well...and Seagate says that:
"Best-Fit Applications"
"Low random-write workloads"
I agree that on the BarraCuda Compute data sheet the recording tech is not clearly communicated.
But that is not the case for Exos Enterprise series. When IT professionals cannot read data sheets and specification sheets, it's their fault.
Since 2017, Seagate's datasheet of Exos 5E8 series state that:
A. "Exos 5E8 ensures archival data confidence with a reliable, low-power data retrieval based on Shingled Magnetic Recording (SMR) technology for..."
B. "Exos 5E8 hard drives are not intended for surveillance or NAS applications, and you may experience lower performance in these environments."
Additionally, since at least November 2016 (when a new logo for BarraCuda, emerged) their respective specification sheet (aka User Manual), state on Recording Technology section, as TGMR (Tunneling Giant Magneto-Resistance) and not Perpendicular as on Exos 7E8 specification sheet.
See for yourself: Data Sheet Exos 5E8, Specifications Sheet - Exos 5E8, Data Sheet - Exos 7E8, Specifiactions Sheet - Exos 7E8, Specifications Sheet - BarraCuda Compute