5 Reasons why the hard drive RPM spec is irrelevant


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I don’t know about you, but I think it’s about time to give up on marketing and positioning hard drives by rotations per minute (RPM).  Here are 5 reasons why the days of marketing the RPM spec in the enterprise/data center space should be over:

1. Customers pay for IOPS, not RPMs.  RPMs or spin speed is just a means to an end. It does not communicate effectively what the disk drive is capable of delivering in terms of performance.  It’s like the old CD-RW drives that were spec’d at 8x, 12x, 24x – and we know those days are long gone.  The real measure of performance is IOPS or Input/Output Operations per Second. If you look at how Rackspace and Amazon market cloud compute, or how quickly Big Data can be analyzed, it’s all about IOPS.

2. The rise of Flash.  When it comes to maximizing IOPS (reason #1), there is no better solution today than flash based storage whether it be DRAM, PCIe, or Solid State Drives (SSDs). No doubt 15,000 RPM and 10,000 RPM server hard drives will have their place for years to come, but we cannot argue against the growth of flash in the IO intensive applications where data is the hottest. Plus RPMs aren’t the reason IT buyers choose to deploy 15K or 10K drives. It’s more about meeting a certain level of IOPS with needed capacity at an attractive cost. This brings rise to our third reason.

3. Hybrid is the best of both words. Whether we are talking hybrid systems or solid state hybrid drives (SSHDs), hybrid storage doesn’t rely on RPMs to market it’s benefits to IT.  It’s all about delivering the right level of performance and capacity, and the ability to move data from flash to disk and back up to flash based entirely on demand for said data. Who really cares if a hybrid system uses 10,000 RPM, 7,200 RPM, or even 5,400 RPM drives?  As long as it delivers on capacity and performance requirements, the RPM spec is irrelevant. You can read more about this in the latest edition of FAST Magazine: Choosing High-Performance Storage is not About RPM Anymore.

4. The Power of power. How many times a day are we bombarded with news on how much data is growing? We get it, it’s huge, and it’s putting more and more pressure on one particular resource that we all know is not infinite –  energy. With fast data growth comes the need to store it somewhere.  Given that most of this unstructured data is cold (accessed infrequently) it does not need to be stored high performance storage.  It belongs on low cost, high capacity storage that consumes less power. Less is more and that’s the power of the power spec.

 5. It’s just plain old. The last time a new hard drive spin speed was introduced was over a decade ago (15,000 RPM), and since then we have seen advancements in areal density which delivers higher capacity and performance, security in the form of self-encrypting drive technology, energy efficiency features like Seagate’s PowerChoice, and let’s not forget interface improvements like 6Gb/s SAS, and now 12Gb/s SAS. In fact, one could argue, spin speed or RPM has not changed at all.  In the fast moving world that is information technology, innovation is critical, and when it comes to how fast we can spin some platters, it just isn’t there.

Long live touting innovations that actually deliver greater capacity, higher IOPS, lower power, and relevant features that IT Pros are willing to pay for, because RPM just ain’t cutting it anymore.


Related Posts:

The TCO of Hard Drives vs Flash Storage…not so fast

Seagate puts Big Data in action – a case study

Over-paying for over-performance?



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  1. Charles May 12, 2013 at 8:59 am - Reply

    Yes, you are right RPMs might be the wrong stat but in many ways its what the consumer is accostomed to and it can take a while to re-educate your consumer base. Megapixels isn’t the best stat to sell cameras on, but that is what the customers are use to so it continues, likewise lightbulbs are still sold on watts or what I’ll calll their ‘watt equivilent’ when really they should be sold on lumens, but the general public doesn’t quite understand what a lumen is.

    Its not entirely like telling someone who grew up in the US that it is currently 20 C outside. Most people will not have a good understanding of what that means because they have no internal calibration for that scale.

    I suspect the RPM number will continue to be on packaging for a while yet, even if those in the know realize it no longer (if it ever did) means anything.

  2. Bob September 22, 2013 at 11:18 pm - Reply

    While i partially agree with you in terms of certain devices like SSDs and other flash devices. Your forgetting something relatively important… hard drives obviuously are not like SSD or flash drives and have moving mechanical parts compared to the latter which have no moving parts. So the only way one can measure I/O, seq reads and seq writes on a mechanical hard drive is through disk spindle speeds (rpms).

    Which is proven time after time that the rpms do affect a HDD performance. Bringing me to my point that if companies like WD, Seagate, Hitachi, etc not display the RPM of there mechanical hard drives then there is no way to tell the difference in performance of that hard drives expect from word of mouth (which can be misleading and unreliable).

    So while you say it is not needed, it actually is for as long as there is mechanical hard drives. Sure you could just print the I/O instead but then people will question why is hard drive (a) noiser than hard drive (b) and will likely replace hard drive (b) for a quiter hard drive not realizing that the actual reason (b) is noiser and offers better performance than (a) is because (b) is running at 15000rpms and (a) is only running at 7200rpms.

  3. Steve September 28, 2013 at 9:58 am - Reply

    I agree that rpm can be irrelevant for small files.

    However, if you are copying a 30GB file to or from a hybrid drive with only 8GB of NAND wouldn’t a 7200rpm drive copy it faster than a 5400rpm drive?

  4. njane July 3, 2014 at 4:06 am - Reply

    so, whats the equivalence of 7200rpm rated hdd interms of IOPS??

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