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From the blog:

"The data intensity of typical small business/home NAS workloads is intermittent, leaving sufficient idle time for DMSMR drives to perform background data management tasks as needed and continue an optimal performance experience for users."

A NAS drive, which features RAID specific firmware no less, is _very_ likely to be put in a RAID, and rebuilding the RAID after replacing a disk is exactly the opposite of an intermittent workload.

What they should have done is this:

- Change the name slightly, "WD Red Lite" or something.

- Make sure the product information page (and firmware if applicable) says this is a DM-SMR drive.

- Say it is intended for single-disk or RAID-1 (mirror) setups, and is not recommended in RAID-5, RAID-6 or similar setups, with links to their Red Pro disks for that.

That would allowed them to capitalize on the "WD Red" name as something consumers have heard about, while also not right out lying about a very important aspect of the product.

If you change the name to "lite" the jig is up and everyone knows it's a poorer quality product than what they're used to buying. By keeping the same name they can increase margins by duping unsuspecting buyers into buying a poorer quality product.

Maybe "Red Lite" is a poor name, maybe "Red Home" is better.

Either way yeah this was an attempt at a cash grab. Which was quite stupid, because there's no way they'd be able to hide the fact that it's SMR for long, the performance characteristics is just too different.

But it's also totally unnecessary, because SMR is perfectly fine for use-cases with sparse random write workloads. Something most casual home users or small businesses with a 1 or 2 disk Synology or similar has.

They already created Red Pro for business use, and market it as "Designed and tested for RAID environments 8-16 Bay NAS", at a 37% markup relative to the Red in my market. My quick Google sleuth indicates those are not SMR. The Red line is marketed as "Designed and tested for RAID environments 1-8 Bay NAS", which implies they're for more than just a 2-bay Synology box.

An Ethical company, with Ethical Marketing would do that

WD has proven they are anything but ethical with this move, I moved from Seagate to WD awhile back for many of my personal drives, looks like it is time to move back to Seagate or Toshiba from now on..

I dropped WD after buying, and returning, their WD MyCloud Home device.

I expected, per their advertisements, a cheap barebones LAN visible NAS with SMB shares.

What i got was basically a self hosted google drive that: - doesn't work without internet even on LAN - can be accessed as SMB share only with WD spyware installed! - WD spyware crashed my graphics drivers - WD spyware works only when there is internet connection available - can be only managed via internet - costs more than space on any cloud storage provider for self hosted solution - you have utter lack of privacy as they scan, and analyze each file on your drive as per their ToS, same thing with their application - hence i call it spyware.

Both Seagate and Toshiba do the same. You have nowhere to move.

Kinda... They do sell undisclosed SMR drives into the Desktop and external Space, but they both have come out to Affirm that they do not do that in the NAS space

https://arstechnica.com/information-technology/2020/04/seaga...

Seagate will happily brick your drives with bad firmware. Toshiba is it.

Yah, the idea that someone at WD thought it a good idea to put these kinds of drive in a RAID means that they don't technically understand RAID. Which is sort of scary, and makes you wonder what other gocha's they have lying about.

Even regular idle scrubbing is going to potentially keep drives 100% busy for extended periods of time. Combined with online backup/etc. Its crazy! Do they think that only enterprises run their NAS'es with backup, or workloads that provide a low level of near constant background activity?

Doesn't seem like it would work in a RAID1 setup: a rebuild typically requires reading the entire source drive and writing it to the other drive in the mirror. Some filesystems like ZFS might understand where the used blocks are and only copy them, but others where RAID is a layer above the filesystem (Linux mdadm) will have to copy the whole drive, even if it's empty.

Pretty much exactly my thoughts. This is the diesel "cheat device" of magnetic disk recording.

This kind of behavior really annoys me and I hope the market brutally punishes them for it, but I'm not holding my breath.

I haven’t been buying WD for my home projects for a long time. But they now own HGST Ultra/Deskstar line and will likely make it suck.

Toshiba has the 3.5" HGST tech [0] so you can buy a toshiba drive if you are afraid WD will ruin the HGST technology they bought.

0: https://en.wikipedia.org/wiki/HGST

> Also note that they talk about these being "drive-managed SMR" drives, and they are, but they reportedly don't advertise themselves to the OS as being drive-managed SMR, as they're supposed to do as per the ATA specifications (unlike other WD DMSMR drives which do). They literally designed the drives themselves to lie about this.

I wonder if reporting to the OS that it is a SMR drive would kick in host-managing SMR code paths that conflict with how the drive managed SMR works. While I'm not terribly inclined to give WD the benefit of the doubt, this seems certainly possible. It seems like it should be possible to test by modifying whatever part of the Linux kernel or userspace tools control this and having it use the model number instead of what the drive reports as its SMR status. Granted on a closed device like a Synology NAS, this isnt possible for a user to do though Synology themselves could, and probably should test this.

From what I've been reading the main difference is simply exposing the TRIM command, which can in no way be a detriment - the only reason to disable TRIM is to hide the fact that it's SMR

Interesting! I never would have thought of a spinning drive as needing a TRIM command, but it makes sense for drives where data is literally overlapping.

But, why would failure to expose TRIM cause errors in in rebuilding a RAID, in which case old drives should be more or less read-only, and replacement drives write only? My understanding is that TRIM should affect re-writing sectors only.

TRIM isn't the cause. The problem with SMR is that disk failure in a RAID array causes read/write patterns during a rebuild that SMR simply was not designed for. I'm sure SMR friendly RAID software will be available in the future for but this requires the software to know that the drive uses SMR. SMR also tends to have really awful performance for regular desktop usage.

Yah, by blocking foreground read/write activity until an entire SMR region has been filled. That will work well...

Sorry what I meant was the difference between host-managed and DMSMR. Having TRIM doesn't make any difference in the rebuild, it just means you can detect it's SMR and you can help the drive in normal usage. Either one will have trouble in a RAID rebuild. Being able to detect it's an SMR drive could probably let some RAID software handle it in a better way, but I don't think any existing software does (since nobody is crazy enough to use SMR in a RAID)

In theory, SMR drives shouldn't have issues with reading and they should also write fine if you write entire stripes. With HMSMR it should be possible. With DMSMR - I don't know. Do DMSMR drives partially skip staging area on large writes and fully if you align them?

I don't see why RAID rebuilds should take notably longer on SMR drives, if only they were properly managed - by both the RAID driver and drive FW. Though it's hard to properly utilize a DMSMR black box.

RAID's are generally rebuilt online. Which means that the normal read and write activity is still occurring. Rewriting a block of data in the middle of a SMR region requires reading the entire SMR region, updating the changed data and then writing it back. So, normally a raid controller will just stop updating a strip (frequently much much smaller than a SMR region) and perform whatever forground activity is needed. The smarter ones rebuild the the strip of the new data along the way. This is going to really mess up rebuilding on SMR because suddenly what you assume is probably a linear operation isn't from the perspective of the drive.

TRIM is not involved when RAID is rebuilding. You are correct in that.

Cannot agree more. IMO, SMR based drives should be used for archiving purpose only. It does not fit for day to day usages, and not even think of using it in NAS/RAID.

But guess what: there’s literally no other options when it comes to spinning rust, WD owns most of the brands.