Who makes the best disk drives?

Who makes the best disk drives?

Summary: Finally, someone with enough volume to test significant numbers of drives comes clean. There are drives to buy and drives to avoid.

TOPICS: Storage, Hardware

Backblaze - the cloud backup company - continues to share their drive experience (see Build an 180TB storage array for $1,943*How long do disk drives really last? and Enterprise disks: worth the money?) with us onesy-twosy buyers. It's informative.

Backblaze, which open sourced their Storage Pod a few years ago, is now giving drive failure rates. They currently have over 27,000 consumer grade drives spinning in Backblaze storage pods.

Almost 13,000 each are Seagate and Hitachi drives, almost 3000 Western Digital drives and a too small for statistical reporting smattering of Toshiba and Samsung drives.

One cool thing: Backblaze buys drives the way you and I do: they get the cheapest drives that will work. Their workload is almost hundred percent write. Because they spread the incoming writes over several drives their workload isn't very performance intensive either.

Also, like you and me, they are willing to spend a little more for a more reliable drive but not a lot more. And unlike you and me they track every single drive that they install.

They measure the annual failure rate (AFR) rather than MTBF because that's an easier number to understand. They count as a failure anytime they have to replace a drive. Of course, vendors report that about half of all returned drives have no trouble found – but I like Backblaze's definition better.

The bad news
Annual failure rates are all over the map ranging from as low as 0.9% to as high as 25.4% - and one drive hit 120%. But the huge majority of drives that Backblaze has installed over the last four years are still operating.

Backblaze excluded some drives from the results because they just don't work at all in the Backblaze environment. These are some of the so-called green drives – WD's 3TB Green drives and Seagate's LP (low-power) 2TB drives.

Backblaze is not equipped to do root cause analysis on drive failures so they don't know the reasons for the problems. Other Seagate LP drives have been quite reliable, which points up the limits of blanket assumptions about an entire model family.

Hall of shame
In general, Backblaze sees more problems with Seagate drives than the other two vendors. Yet those problems have been getting better with each successive generation of high-capacity drives.

But the 1.5 TB Seagate Barracuda 7200 and the Seagate Barracuda Green have the highest AFRs, 25.4% and 120% respectively. And in general the Seagate drives have proven to be less reliable overall.

Hall of Fame
Hitachi drives have proven to be the most reliable. Their annual failure rates have ranged from .9% all the way up to 1.5%.

Of course Hitachi drives typically cost more. Maybe you do get what you pay for.

In the middle are the Western Digital drives with AFRs ranging from 3.2% to 7.3%. Of course, WD will take full control of Hitachi in a few months and I suspect that we will see Hitachi's failure rates approximate those of WD over time.

Here's the Backblaze table of results:

Courtesy Backblaze

The Storage Bits take
All large drive buyers and the vendors track reliability. But long ago the industry decided not to share this information with consumers.

Backblaze is to be commended for breaking the industry-wide code of silence. Our digital data is too precious for consumers to be left in the dark.

You may wonder why Hitachi who has long had a reputation for good quality is the company that was acquired. Industry scuttlebutt has it that Hitachi's yields - the percentage of shippable drives compared to starts – was the lowest in the industry. This left them with high costs and their profitability suffered. People just weren't willing to pay for quality.

Sound familiar?

It is encouraging that Seagate's 4TB drive AFRs are more in line with the competition. Perhaps they had some manufacturing hiccups with earlier drives. And remember, these are 3.5" drives: notebook drives may be different.

But perhaps, like Backblaze, you will choose to buy the lowest cost drive that offers reasonable reliability. Backblaze still buys a lot of Seagate drives and there is nothing in this report that would cause me not to buy Seagate either.

But for my RAID array? Yeah, I like Hitachi.

The bottom line is that there is no substitute for backing up your data. Even in the most reliable drives do fail and if you haven't back up your data it is you - not the vendor - who is the loser.

Comments welcome. Are there any surprises in this data for you? Read the entire Backblaze blog post.

Topics: Storage, Hardware

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  • "People just weren't willing to pay for quality."

    Maybe if more people had known that the Hitachi drives were significantly less prone to failure, they would have paid extra for them.
    Jack Schofield
    • I agree

      Had I had these stats I would of bought more Hitachi, I bought more Seagate as I have had good experience with them. Just like I did when IBM made drives till they were bought up. Have been buying more WD's lately, but that is because of price and performance.
      • I stopped buying the Deskstars when IBM screwed them up ...

        For some time I was buying IBM Deskstars and was REALLY happy with them. Then I ended up with a pair of 40GB drives that failed in no time. Within months of that happening, IBM had sold the drive business to Hitachi. But I steered clear of Deskstars from then on and went over to Seagate. What I have found with Seagate is that some of their drive products last forever ( I am still using Seagate drives purchased well over ten years ago), and other times they have proven to be barely capable of making the warrenty and at least on one occasion didn't. So my experience with Seagate has been mixed. What I cannot handle with Western Digital is their quirkiness when it comes to standards. Like 4K drives that read out as 512s, etc. But it is heartening to know that Hitachi has the Deskstar line back in shape again. I will definitely keep that in mind.
        George Mitchell
        • Ah, the old...

          ...DEATHSTAR !!!

          I stopped buying Hitachi when every disk didn't last more than a little over a year. Never had an issue with WD, but recently have installed a couple of 4T Seagates in my server - because they were cheaper.
          • Issues with WD & Seagate

            Almost every Seagate I used in the 80's froze up and quit working and throughout the 90's I was sending in WD's all the time for failures. I thought they might get on my case I sent so many in each year. I was sending in for Me, My brother, My niece and my mom... I quit buying WD's for a while... Thinking about it, I don't know what I have in my computers right now but we haven't had failures in quite a few years now....
            Jeanne L
        • Deskstar

          If I am not mistaken, Hitachi were THE OEM suppliers to IBM. Of course, Hitachi sold their HDDs directly to end users in their own name as well as to others. After IBM, Hitachi continued to use their 'Deskstar' and other 'IBM' names.
          P K Pal
    • This is not new news

      If you have been in IT long enough you know that Seagate is a drive you avoid. This was confirmed a few years ago by a report published on Toms Hardware by a Russian company that does HD recover. They stated that it was not a scientific study but they released what they have seen regarding HD and which are best. It mirrored this report here. Hitachi was best and Seagate was the bottom of the barrel. I have only bought Hitachi from that point forward, the price difference is not that great and the quality is far better. WD is not bad but I do fear they will bring down the quality of Hitachi rather then letting WD quality in crease.
    • People don't pay for quality, people just want cheap. Market Forces Rule.

      Market Forces rule... People buy cheap... It's really bad news.

      I use small numbers of drives, but I ALREADY KNEW Hitachi were good and Seagate were bad, just by looking at the label on dead drives I removed vs. working drives inside decommissioned machines.

      Pus I noticed IBM installed Hitachi drives in the servers I chose to pay more for.

      But most people buy the cheap DELL servers... In their millions.

      The entire PC market has been driven to the low-cost semi-disposable Windows computers that are crap and/or broken after +/- 3 years and get replaced by a new machine & new O.S.

      However, I buy good IBM servers with decent drives and expect them to stay running 5-10 years. Go figure.

      It's actually a lot simpler and a lot more obvious than people think -- but most people want cheap, despite what they claim. Look what the article says about "most people buy on price" and will only pay "a little more for reliability"... Not me, I don't buy crap that'll die after a bit of use, I expect to spend proper money and then have the kit last for extended periods of time.
  • Need to pick apart this data for a moment

    Seagate doesn't sell a lot of those models anymore, and they issued a big statement about getting out of so-called "green" drives because they had statistics that showed that the small savings in power didn't compensate for the lack of performance, or the additional wear on the motor from constantly spinning up and down. WD still does though, and I can tell you I won't be buying anymore WD drives after the flood caused them to mark down warranties from moving manufacturing out of their main factory. Seems that WD didn't have a lot of faith in the QA of their new digs.

    Overall, I've been happy with the reliability of Seagate's new SSHD's (not the old XT line) when building systems. I haven't once received a bad one from a distributor, whereas my last lot of WD Blue and Green drives before the flood had about a 10% DOA rate.

    Oh, and as far as Hitachi drives go, I had 15 out of about 35 drives fail in the last 3 years, and 4 of those completely borked the RAID arrays they were in, so I've sworn them off.

    Also, I want to pick this line apart: "Backblaze buys drives the way you and I do: they get the cheapest drives that will work"

    So, basically NewEgg? I dunno why they would buy from a 2-bit wholesaler instead of an authorized distributor. I also don't get why NewEgg has such shoddy reliability with their parts, but I suspect that their shipping department throws crap around in the warehouse because I know too many people that have bought parts from there for a PC build and what seems like 80% of their order has to go back because it's DOA. I actually know one guy that bought stuff to do a PC build, and his power supply, video card, and RAM all had to be returned, and his motherboard had to be returned TWICE.
    • NewEgg

      Sorry to hear about your issues with NewEgg. In the 10+ years I've been buying from them I have built 15 PCs, and have yet to receive a DOA component. As for the one guy who had to return everything, it sounds like he probably assembled things poorly and fried the parts. DOA parts do get shipped, but the odds of all the components in one order being legitimately DOA are very slim.
    • Everybody has their own story

      My story is that I've never had to return a purchase to Newegg for DOA (none).

      The cause could be good luck, or maybe it's because I only buy components with high ratings (and good DOA feedback).
    • Really?

      I've been buying lots of parts from Newegg since they started, and I've never experienced anything like what you're saying! Anyone who has to return 80% of his order is either not being truthful, did something to wipe them out, or there was some environmental factor he's not telling you about. For example - had to send 80% of the order back after retrieving the box from his basement after Katrina!

      I've had remarkably good luck with Newegg, and the few times I've had any issues, they were helpful and took care of it
    • Newegg

      Yev from Backblaze here -> We actually buy from both. We try to get the cheapest price possible. Sometimes it's through distributors, but if Newegg/Amazon/B&H have a sale, we'll be all over it. Price is one of our biggest factors, so if we can lower it somehow, we'll try to!
    • Thats why large samples are important.

      And a large controlled environment where metrics are taken and people are actually tracking the data.

      So thousands vs a few dozen with a very controlled environment and meticulous metrics wins me every time.

      Maybe your raids need better cooling?

      I've had good results from NewEgg
    • Huh?

      I've ordered many many parts for my PC build from Newegg and I've never had to return anything. I've been ordering from Newegg for close to 10 years now. Your whole comment sounds like a load of crap. Newegg is not some 2 bit wholesaler. They offer good customer service with a good return policy and they are very successful.
  • How are calculations done?

    How on earth can 120% of the drives fail? If I installed 100 drives, how can 120 of them fail?
    • it is an annual thing

      You could have drives fail multiple times in a year. In other words they went through 120 drives.
    • Magic?

      You install 100 drives. They all fail and you send them for repair/replacement. You receive 100 new drives and 20 of them fail.

      120% failure rate.
      • Wrong Math

        You install 100 drives. They all fail and you send them for repair/replacement. You receive 100 new drives and 20 of them fail.

        120% failure rate.


        No, that's completely wrong.

        You have received 200 drives (the original 100 and the 100 replacements)
        120 of them failed (100 in the first batch, 20 in the second batch)

        That's 120 failures out of 200 drives = 60% failure rate.
        • Nope.....you are wrong

          You only purchased 100 drives. What you send to repair, you expect to get back. That is, it's the SAME drive (whether or not it ACTUALLY is).

          If your TV breaks down and you send it for repair, anything up to 100% of it may be replaced. When you get your TV back, you still only have 1 TV.

          By your math, it would never be possible to count 120% failure rate.