Discussion External (portable / 2.5") hard drives and how to avoid SMR

[mikeymikec]

I posted this thread a few years ago:

Does anyone have a new Seagate portable USB 3.0 drive to test with?

I'm puzzling over the very hit-and-miss performance of a drive I've just bought for a customer. Here's a benchmark I did just now: The drive on the left is my own Seagate portable drive that I bought a few years ago that I have no problems with. The drive on the right is the one I've just...

forums.anandtech.com

I thought it would be better to start a new one as the old thread title isn't that helpful for this topic. I started using Toshiba Canvio Basics drives as a result of that thread and all seemed good for a while, but I've since noticed that at least one of the drives uses SMR tech because a large data backup's throughput went to pot. I checked the SMART data, looked up the drive model, and sure enough, Toshiba has jumped on the SMR bandwagon (not sure when). I suspect the 2TB model also uses SMR as a result of a recent experience but I'd need to check the model of those drives I sold recently to be sure.

As I'm not aware of any HDD manufacturers that are marketing non-SMR external hard drives, it seems to me that I'd either be relying on word-of-mouth recommendations that are a) temporary (ie. a manufacturer could at that moment be using CMR drives, then later change to SMR), and/or b) dependent on the recommender's ability to spot an smr drive. I'm thinking the best way forward is to start buying 2.5" USB3 enclosures and the drives separately, after obviously checking the drive's model number to ensure that it's not SMR. That's of course assuming that there are still CMR 2.5" HDDs available, which I'll start checking

I find this whole cloak-and-dagger business the HDD manufacturers are playing to be a bit odd though. At the end of the day, the most obvious reason to get a portable HDD over a high capacity USB flash drive is performance, and then the HDD manufacturers go and tank their drives' performance in the name of saving a little money. It still leaves a niche in the market for people who do want better performance, so why on earth don't the HDD manufacturers market a 'ultra high performance' portable HDD? Another alternative one might argue is an external SSD, but considering that SSD manufacturers also like to play similar silly games with their SSDs, it's basically the same problem with a different tech name, that's just aside from a 1TB external SSD seemingly being triple the price of a 1TB portable HDD.

 

[mikeymikec]

Wow, all of Seagate's 2.5" current HDDs are SMR apparently!

CMR and SMR Hard Drives | Seagate UK

See the list of recording technology utilised on our internal hard drives

www.seagate.com

I guess that speeds up my search

Toshiba still sells some CMR drives (and some SMR):

https://www.toshiba-storage.com/products/toshiba-internal-hard-drives-l200/?pdf

It looks like a quick indicator when browsing drives is the size of the cache - the SMR variant of the 1TB L200 drive has 128MB cache whereas the CMR variant has 8MB. As I understand it, the larger cache is an attempt to offset the poorer performance of the tech. HWDJ model drives seem to be CMR, HDWL seem to be SMR.

WD doesn't make it easy seemingly.
WD5000LPCX ("WD Digital AV") - This model has a 16MB cache so I suspect its CMR, but I haven't yet got a hit for that model on the WD site.

This one definitely is SMR:
WD10SPZX - https://blog.westerndigital.com/wp-content/uploads/2020/04/2020_04_22_WD_SMR_SKUs_1Slide.pdf
128MB cache, so I suspected as much.

WD Blue rule of thumb #2: PZX model drives are likely to be SMR.

WD10JUCT not sure about this one, according to a third party site it's CMR and the low cache size suggests that's correct.

WD Blacks are a mix of CMR and SMR according to this:

https://www.westerndigital.com/products/internal-drives/wd-black-mobile-sata-hdd

PSX's are likely to be SMR, PLX's are likely to be CMR, seems to be a good rule of thumb. Why are there any SMR WD Blacks in existence... again the cache size seems to be a good giveaway, 32MB cache for CMR and 64MB for SMR.

I'll keep updating this post as I trawl through one of my supplier's list of 2.5" HDDs.

 

[Charlie98]

Interesting.

Looking back at your old thread, I had forgotten about the differences in the drives.

again the cache size seems to be a good giveaway, 32MB cache for CMR and 64MB for SMR.

Seems like an easy rule of thumb to follow...

 

[SimplyComplex]

The WD My Passport drives have been SMR since at least 2019. The WD Purple were all CMR as of last year.
The WD Red are SMR now. While the Red+ and Red Pro are CMR.

Last I'd heard, WD drives 10TB+ are all still CMR. Unless something has changed in the last year.

 

[Tech Junky]

WD drives 10TB+ are all still CMR

8TB+ As all below are a mix of either. This might have changed though since SMRgate where all reviews got revisited.

 

[Shmee]

An easy way to avoid SMR is to use SSDs, or make your own external HDD out of a decent HDD and an enclosure.

 

[Tech Junky]

An easy way to avoid SMR is to use SSDs, or make your own external HDD out of a decent HDD and an enclosure.

I would equate easy with common sense. We all know it's not so common though.

 

[BonzaiDuck]

I would equate easy with common sense. We all know it's not so common though.

I acquired some aluminum external HDD/ODD enclosures built by Thermaltake around 2005. I have some five or six of them, with USB2 interface. I converted some of those to eSATA with some minor mods -- still powered by the original hardware, but the USB2 interface is disconnected. That's where my 3.5" HDD "pulls" go if they're in tip-top condition. Any recommendations for external DIY enclosures for 2.5" spinners and SSDs?

 

[mikeymikec]

@BonzaiDuck

I've been using a very cheap 'Inateck' model FE2004 self-powered USB 3.0 enclosure without issues, it can also handle the more recent Samsung SATA SSDs that my old dock couldn't handle.

My only criticism of it is that the side that one inserts the drive in is really the underside but logically I'd prefer to run a HDD 'right side up', then the drive access light is on the wrong side of the enclosure. Not really a big deal as one can monitor throughput in Device Manager.

 

[PingSpike]

An easy way to avoid SMR is to use SSDs, or make your own external HDD out of a decent HDD and an enclosure.

You still have to identify CMR drives even if you buy the bare drive though.

I know I wanted some CMR 2.5" HDDs and it didn't even seem like new ones existed when I was looking. Maybe toshiba had some?

 

[Shmee]

You still have to identify CMR drives even if you buy the bare drive though.

I know I wanted some CMR 2.5" HDDs and it didn't even seem like new ones existed when I was looking. Maybe toshiba had some?

Yeah this is a good point, and I guess also a good argument for only buying SSDs for 2.5 in drives. Another one being that 2.5 in HDDs are generally even more fragile than 3.5 in ones, and often aren't nearly as fast, and generally don't come in higher capacities. A 1TB SATA SSD can be had for under $100 at most times these days, even for a pretty good one.

 

[Tech Junky]

You can get 2.5 SSD's:

$100/TB


NVME Speeds / 5X SATA at least at higher capacities run about $150/TB


You can get whatever you want in terms of speed / capacity if you're willing to pay for it. Chips vs Platters. There's also the option of pairing up 2 NVME's in an enclosure the size of a 2.5" SSD.

 

[mikeymikec]

One thing to also bear in mind is that "just buy an SSD" is not a sure-fire way of solving the problem as the SSD market is also scraping the barrel for the worst performance they can muster.

Here's an example of a guy with an SSD complaining that write performance dropped to 30MB/sec:

Question - SSD Write speed drops to 30MB/s after download

I have 240GB Lexar NQ100 SATA SSD and it has still 130GB free, however write speed dropped down to 30MB/s from original 500MB/s. Its also partitioned into two 40GB and 183GB partitions. If i delete about 20 GB of space write speed goes back to normal, what causing this?

forums.anandtech.com

And also bear in mind that SSDs are at least twice the price of a CMR HDD of the same capacity.

 

[Shmee]

Yeah that is true too, not all SSDs are equal, that is certain. Anyone should definitely do their research first. Now it is true to a degree, you get what you pay for. In that sense, better to pay for a half decent SSD, they aren't even that much money. Also, same goes for the enclosure I guess, do your research and get a good one.

 

[mikeymikec]

The WD Red are SMR now.

I thought WD Red was for NAS usage and WD got in hot water over recommending SMRs for NAS?

 

[sdifox]

Why are you even buying external 2.5" hdd in the first place? Just get ext ssd or a big 14TB external hdd. The 2.5" external is a dead category.

 

[mikeymikec]

Why are you even buying external 2.5" hdd in the first place? Just get ext ssd.

https://forums.anandtech.com/thread...es-and-how-to-avoid-smr.2603402/post-40758072

 

[sdifox]

https://forums.anandtech.com/thread...es-and-how-to-avoid-smr.2603402/post-40758072

I am saying it is pointless to get an external 2.5" spinner now.

 

[mikeymikec]

I am saying it is pointless to get an external 2.5" spinner now.

The usual reason I buy them is to supply customers with cheap, high capacity backup systems that are easy to handle. Ignoring SMR for a moment, I normally supplied USB flash drives until the amount of data required for backup reached about 64GB/128GB, then beyond that it tended to make more sense both cost and performance wise to hop straight to a 1TB portable HDD. For my customers, high performance isn't essential but I think there's a sliding scale involving the elements "if it performs faster then the customer is more likely to back up more often" and cost.

IIRC I've never had to help a customer back up more than 1TB of data personally. I've bought maybe 2-3 2TB portable HDDs in total for scenarios like multiple backup sets per drive.

A half-decent 64GB USB flash drive is about £10 UKP, I'd guess that 128GB USB flash is about double the cost, then the average 2.5" portable USB HDD is about £40. A decent CMR 2.5" HDD can sustain >100MB/sec write transfer speeds. I think that's a reasonable argument for its continued existence.

 

[sdifox]

Shingle drives are fine for backup. 3.5" drives live much longer than 2.5". You are paying a form factor premium to go to 2.5" drive. The only 2.5" drive that has an advantage is the 15k rpm server drives, but you are not getting those in an external enclosure.

https://www.amazon.co.uk/Passport-Portable-Technology-Speeds-1050MB/dp/B08F21J716/ref=sr_1_1_sspa?keywords=1tb+ext+ssd&qid=1652185392&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFGSkZDVllSNjFCSE0mZW5jcnlwdGVkSWQ9QTEwNDM5MDkzR004STNKR1hDSjNIJmVuY3J5cHRlZEFkSWQ9QTA3NzczMzkxOEY3SDkzVk42OUhFJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

110 BP for a 1 TB ext ssd is not bad.

 

[mikeymikec]

Shingle drives are fine for backup. 3.5" drives live much longer than 2.5". You are paying a form factor premium to go to 2.5" drive. The only 2.5" drive that has an advantage is the 15k rpm server drives, but you are not getting those in an external enclosure.

https://www.amazon.co.uk/Passport-Portable-Technology-Speeds-1050MB/dp/B08F21J716/ref=sr_1_1_sspa?keywords=1tb+ext+ssd&qid=1652185392&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFGSkZDVllSNjFCSE0mZW5jcnlwdGVkSWQ9QTEwNDM5MDkzR004STNKR1hDSjNIJmVuY3J5cHRlZEFkSWQ9QTA3NzczMzkxOEY3SDkzVk42OUhFJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

110 BP for a 1 TB ext ssd is not bad.

In the thread I referenced at the start of this point, I think there's fair reason for me to not particularly recommend the shaky performance of SSD as an 'upgrade' from flash drives. I'd like to see a citation for your 3.5" claim, but that aside a 3.5" external HDD also requires mains power which makes it more cumbersome as a backup drive for a lot of my (to varying extents) technophobic customers.

SSD: It's also over twice the price, and if the customer is backing up from an internal HDD, then most of the SSD's performance is irrelevant anyway (if in fact it's not a rubbish SSD they've put in there).

I wonder though if an external SSD isn't a bad idea in the event that a customer wanted to back up say 500GB of data, at which point if I follow the logic that I'd rather recommend a HDD over say a 128GB flash drive for performance reasons, then the same logic could be applied once there's enough data to back up that a HDD's performance could become onerous. Having said that, in my experience there's an awful lot of 'not updated often' data in a large enough pool of backup data, e.g. the most likely reason for a customer wanting to back up their personal data are old digital camera photos.

 

[sdifox]

In the thread I referenced at the start of this point, I think there's fair reason for me to not particularly recommend the shaky performance of SSD as an 'upgrade' from flash drives. I'd like to see a citation for your 3.5" claim, but that aside a 3.5" external HDD also requires mains power which makes it more cumbersome as a backup drive for a lot of my (to varying extents) technophobic customers.

SSD: It's also over twice the price, and if the customer is backing up from an internal HDD, then most of the SSD's performance is irrelevant anyway (if in fact it's not a rubbish SSD they've put in there).

I wonder though if an external SSD isn't a bad idea in the event that a customer wanted to back up say 500GB of data, at which point if I follow the logic that I'd rather recommend a HDD over say a 128GB flash drive for performance reasons, then the same logic could be applied once there's enough data to back up that a HDD's performance could become onerous. Having said that, in my experience there's an awful lot of 'not updated often' data in a large enough pool of backup data, e.g. the most likely reason for a customer wanting to back up their personal data are old digital camera photos.

2.5" ext HDD has no performance, cost more per tb than 3.5" ext hdd, has bigger form factor than ext ssd. I just don't see an advantage to them at all.

usb sticks are not reliable enough to be considered backup. And for backup duty, shingle drives are fine, you are not thrashing the drive anyway.

 

[PingSpike]

2.5" ext HDD has no performance, cost more per tb than 3.5" ext hdd, has bigger form factor than ext ssd. I just don't see an advantage to them at all.

usb sticks are not reliable enough to be considered backup. And for backup duty, shingle drives are fine, you are not thrashing the drive anyway.

Isn't the main disadvantage of SMR that is has crappy writes? That seems pretty important for backups to me. Not so important for a media collection, but for drive imaging or other large transfers it's going to be a disadvantage if you do them frequently.

 

[sdifox]

Isn't the main disadvantage of SMR that is has crappy writes? That seems pretty important for backups to me. Not so important for a media collection, but for drive imaging or other large transfers it's going to be a disadvantage if you do them frequently.

Either transfer rate is important, or it isn't.

 

[PingSpike]

Either transfer rate is important, or it isn't.

It's not binary, it's a balance of cost and other attributes. Turning this argument on it's head it's like saying I should only run striped raid arrays of nvme SSDs for backups because I've determined transfer rate is important. It's only important until it's good enough and then it doesn't matter.