7 ms·

You can buy HDDs for $20 / TB. There are companies with millions of TB. Unless SSDs can meet that price point, HDDs have a very comfortable place in society.

by Taek 10y ago

mathgeek 10y ago
I think back to when HDD's were "getting cheaper" at $1/MB (and every power of 10 since at that same price point) and shrug. While they'll certainly still have their place (similar to tape drives and other storage technology that used to be much more commonplace), there's every reason to expect the PPU of SSD's to continue trending downward.
- magila 10y ago
  > there's every reason to expect the PPU of SSD's to continue trending downward Not really. The big driver for cost reduction in SSDs was process shrinks, but the latest processes are actually more expensive per-transistor than older ones so that ship has more-or-less sailed. You've got 3D NAND but that's even more expensive to manufacture so the cost savings are marginal at best. It remains to be seen if XPoint will lead to big savings. In the short term SSD prices have actually been trending up due to a shortage of NAND flash.
  - mathgeek 10y ago
    To my point, this is still the same argument that has been made time and time again with regards to storage. Short term upticks are easy to see in historical SSD pricing, even when looking at the longterm trend. Source: http://www.jcmit.com/mem2015.htm http://www.jcmit.com/mem2015.htm
    - magila 10y ago
      If you think this is the same you haven't been paying attention to what's happening in the industry. Moore's Law as we know it is dead, shrinking the node size isn't cutting costs like it used to. A lot of people are still in denial over this, but it's going to have major repercussions in the IC industry.
      - mathgeek 10y ago
        I'm not referencing Moore's Law at all, nor am I hinging my argument on a single piece of input. I'm simply using decades of historical data to claim that it's more likely to continue downward than upward. Would you mind providing some data points that explicitly or implicitly predict an upward trend over the next 5-10 years?
        magila 10y ago
        I wouldn't go so far as to predict a long term upward trend, but prices are not going to continue their historic exponential drop. Like I said, cost reduction achieved by shrinking the node size (i.e. Moore's Law) was the main enabler for the exponential drop, but that trend has ended. This is common knowledge for anyone who follows the semiconductor industry, if you want data look it up yourself. Prices will surely still drop, but only incrementally. In particular, the PPU of SSDs will not be competitive with HDDs for the foreseeable future.
        mathgeek 10y ago
        Ah, you're not talking about what I'm talking about. That's the issue here. I'm not predicting "historic exponential drop" at all. Glad we can agree that prices will still drop.
toomuchtodo 10y ago
Is that TCO? Because unless you're comparing with warranty, power, and human costs, it's not accurate.
vidarh 10y ago
It's not that simple. How much do you pay to keep those HDDs powered per TB per year? How much does maintenance cost (replacing drives etc.)? How does the low IOPS of those drives affect your workload? SSDs may not win in every area yet, but if you only look at purchase price, you're not getting the right picture.
- gareim 10y ago
  We're talking about a ~10x difference right now. Do your factors sizeably reduce that gap? By how much do you estimate?
- ksec 10y ago
  Yes but when you are looking at Petabyte scale system, unless those data are Hot and IOPs are concerned, HDD still wins given it is 10x cheaper. And NAND has already hit the curve where it isn't going to get cheaper every year. NAND price is actually on the rise. Smaller Node is now actually more expensive, multiple layer are hard to yield. So relatively speaking the 10x gap between HDD and SSD wont change in the next 5 years or so.
  - LeifCarrotson 10y ago
    It is not 10x cheaper, it is only cheaper to purchase initially. It is cheaper to power (NAND is more energy efficient than an electric motor), it is cheaper to maintain (solid state media does not suffer mechanical failures), and it is cheaper to use (each query on an SSD takes slightly less time than on spinning media). It's only 10x cheaper if you ignore those facts. Now, how you value those factors may vary. Also, I have been involved in enough purchasing decisions to know that while capex is easy to approve and opex is hard, the initial number is surprisingly important.
    - sandworm101 10y ago
      I think you overestimate the cost of electricity over the expected life of a drive. These arent space heaters. Pennies per day, adding up to perhaps tens of dollars difference between the two options.
bogomipz 10y ago
That is not true. If your content has a really long tail then you also likely also have a tiered storage where hot content is stored in the page cache and NAND(near storage) and much less frequently accessed is on HDD(far storage.)
castratikron 10y ago
You are correct in that hard drives are still an order of magnitude cheaper per unit of storage than solid state drives. Then again, tape drives are still an order of magnitude cheaper per unit storage than hard drives. When was the last time you saw a tape drive?
- Tsiklon 10y ago
  ... under my desk.
- tim333 10y ago
  >tape drives are still an order of magnitude cheaper Are they though? I just searched on Amazon and the cheapest LTO6 drive was $1,619.56. Even just the tapes are $25 or so for "(2.5TB) native to (6.25TB) compressed" whatever that means which I guess is cheaper per TB if you don't worry about the drive. https://www.amazon.com/Quantum-Ultrium-6-Drive-Height-Internal/dp/B00F0RJ2XY/ref=sr_1_3?ie=UTF8&qid=1484407571&sr=8-3&keywords=tape+drive https://www.amazon.com/Quantum-Ultrium-6-Drive-Height-Intern... https://www.amazon.com/Sony-Linear-0-85-Inch-Internal-LTX2500G/dp/B00ARHKUZG/ref=pd_sbs_23_3?_encoding=UTF8&pd_rd_i=B00ARHKUZG&pd_rd_r=3BD9W2GKMW1J99AK0A9K&pd_rd_w=VGNGJ&pd_rd_wg=ImhCO&psc=1&refRID=3BD9W2GKMW1J99AK0A9K https://www.amazon.com/Sony-Linear-0-85-Inch-Internal-LTX250...
- Taek 10y ago
  The tape industry is still billions of dollars per year. Enterprises still buy tape all the time, and tape technology is still iterating. And tape is not even that competitve. It's like 1/3 the cost of HDDs, and has an 80 second seek time, making it completely unusable for most real time applications (still usable for theatrical movies).
  - ams6110 10y ago
    Tapes are still used for enterprise backup, and for hierarchical storage systems (e.g. hot data on SSD, warm data on HDD, cold data migrates to tape eventually).
- hyperbovine 10y ago

You can buy HDDs for $20 / TB. There are companies with millions of TB. Unless SSDs can meet that price point, HDDs have a very comfortable place in society.

by Taek 10y ago

You can buy HDDs for $20 / TB. There are companies with millions of TB. Unless SSDs can meet that price point, HDDs have a very comfortable place in society.

mathgeek 10y ago

I think back to when HDD's were "getting cheaper" at $1/MB (and every power of 10 since at that same price point) and shrug. While they'll certainly still have their place (similar to tape drives and other storage technology that used to be much more commonplace), there's every reason to expect the PPU of SSD's to continue trending downward.

magila 10y ago
> there's every reason to expect the PPU of SSD's to continue trending downward Not really. The big driver for cost reduction in SSDs was process shrinks, but the latest processes are actually more expensive per-transistor than older ones so that ship has more-or-less sailed. You've got 3D NAND but that's even more expensive to manufacture so the cost savings are marginal at best. It remains to be seen if XPoint will lead to big savings. In the short term SSD prices have actually been trending up due to a shortage of NAND flash.
- mathgeek 10y ago
  To my point, this is still the same argument that has been made time and time again with regards to storage. Short term upticks are easy to see in historical SSD pricing, even when looking at the longterm trend. Source: http://www.jcmit.com/mem2015.htm http://www.jcmit.com/mem2015.htm
  - magila 10y ago
    If you think this is the same you haven't been paying attention to what's happening in the industry. Moore's Law as we know it is dead, shrinking the node size isn't cutting costs like it used to. A lot of people are still in denial over this, but it's going to have major repercussions in the IC industry.
    - mathgeek 10y ago
      I'm not referencing Moore's Law at all, nor am I hinging my argument on a single piece of input. I'm simply using decades of historical data to claim that it's more likely to continue downward than upward. Would you mind providing some data points that explicitly or implicitly predict an upward trend over the next 5-10 years?
      - magila 10y ago
        I wouldn't go so far as to predict a long term upward trend, but prices are not going to continue their historic exponential drop. Like I said, cost reduction achieved by shrinking the node size (i.e. Moore's Law) was the main enabler for the exponential drop, but that trend has ended. This is common knowledge for anyone who follows the semiconductor industry, if you want data look it up yourself. Prices will surely still drop, but only incrementally. In particular, the PPU of SSDs will not be competitive with HDDs for the foreseeable future.
        mathgeek 10y ago
        Ah, you're not talking about what I'm talking about. That's the issue here. I'm not predicting "historic exponential drop" at all. Glad we can agree that prices will still drop.

toomuchtodo 10y ago

Is that TCO? Because unless you're comparing with warranty, power, and human costs, it's not accurate.

vidarh 10y ago

It's not that simple. How much do you pay to keep those HDDs powered per TB per year? How much does maintenance cost (replacing drives etc.)? How does the low IOPS of those drives affect your workload? SSDs may not win in every area yet, but if you only look at purchase price, you're not getting the right picture.

gareim 10y ago
We're talking about a ~10x difference right now. Do your factors sizeably reduce that gap? By how much do you estimate?
ksec 10y ago
Yes but when you are looking at Petabyte scale system, unless those data are Hot and IOPs are concerned, HDD still wins given it is 10x cheaper. And NAND has already hit the curve where it isn't going to get cheaper every year. NAND price is actually on the rise. Smaller Node is now actually more expensive, multiple layer are hard to yield. So relatively speaking the 10x gap between HDD and SSD wont change in the next 5 years or so.
- LeifCarrotson 10y ago
  It is not 10x cheaper, it is only cheaper to purchase initially. It is cheaper to power (NAND is more energy efficient than an electric motor), it is cheaper to maintain (solid state media does not suffer mechanical failures), and it is cheaper to use (each query on an SSD takes slightly less time than on spinning media). It's only 10x cheaper if you ignore those facts. Now, how you value those factors may vary. Also, I have been involved in enough purchasing decisions to know that while capex is easy to approve and opex is hard, the initial number is surprisingly important.
  - sandworm101 10y ago
    I think you overestimate the cost of electricity over the expected life of a drive. These arent space heaters. Pennies per day, adding up to perhaps tens of dollars difference between the two options.

bogomipz 10y ago

That is not true. If your content has a really long tail then you also likely also have a tiered storage where hot content is stored in the page cache and NAND(near storage) and much less frequently accessed is on HDD(far storage.)

castratikron 10y ago

You are correct in that hard drives are still an order of magnitude cheaper per unit of storage than solid state drives. Then again, tape drives are still an order of magnitude cheaper per unit storage than hard drives. When was the last time you saw a tape drive?

Tsiklon 10y ago
... under my desk.
tim333 10y ago
>tape drives are still an order of magnitude cheaper Are they though? I just searched on Amazon and the cheapest LTO6 drive was $1,619.56. Even just the tapes are $25 or so for "(2.5TB) native to (6.25TB) compressed" whatever that means which I guess is cheaper per TB if you don't worry about the drive. https://www.amazon.com/Quantum-Ultrium-6-Drive-Height-Internal/dp/B00F0RJ2XY/ref=sr_1_3?ie=UTF8&qid=1484407571&sr=8-3&keywords=tape+drive https://www.amazon.com/Quantum-Ultrium-6-Drive-Height-Intern... https://www.amazon.com/Sony-Linear-0-85-Inch-Internal-LTX2500G/dp/B00ARHKUZG/ref=pd_sbs_23_3?_encoding=UTF8&pd_rd_i=B00ARHKUZG&pd_rd_r=3BD9W2GKMW1J99AK0A9K&pd_rd_w=VGNGJ&pd_rd_wg=ImhCO&psc=1&refRID=3BD9W2GKMW1J99AK0A9K https://www.amazon.com/Sony-Linear-0-85-Inch-Internal-LTX250...
Taek 10y ago
The tape industry is still billions of dollars per year. Enterprises still buy tape all the time, and tape technology is still iterating. And tape is not even that competitve. It's like 1/3 the cost of HDDs, and has an 80 second seek time, making it completely unusable for most real time applications (still usable for theatrical movies).
- ams6110 10y ago
  Tapes are still used for enterprise backup, and for hierarchical storage systems (e.g. hot data on SSD, warm data on HDD, cold data migrates to tape eventually).
hyperbovine 10y ago