Enterprise SSDs

Five-Minute IOPS Survey

Asking for Help with the Coughlin Associates/Objective Analysis IOPS Survey

Tom Coughlin of Coughlin Associates and Yours Truly: The SSD Guy are once again polling as many IT professionals as we can with a very simple 5-minute survey asking about your IOPS needs.

This is an update of the same survey we ran in 2012.  We want to see how things have changed over the past four years.

Please click HERE and let us know what kind of storage performance you need. Even a hunch is good.

Many thanks!

Why 3D XPoint SSDs Will Be Slow

SNIA: Sources of SSD LatencySomething that has been confusing a number of people is the performance of Intel’s 3D XPoint-based SSDs.  Why are they so slow?

Let me back up a little – they’re not really slow.  When Intel compared its standard NAND flash based PCIe SSD to a similar SSD based on 3D XPoint memory, the XPoint model ran 7-8 times faster, which is very impressive.  Intel demonstrated that at the Intel Developer Forum (IDF) last August and several times since then.

But Intel and Micron have been boasting since its introduction that 3D XPoint Memory is 1,000 times as fast as NAND flash.  How do you get from a 1,000 times speed advantage down to a speed improvement of only 7-8 times?

That’s what the graphic in this post will explain.  The small rendition above is just Continue reading

Why SSD and HDD Prices Move in Parallel

ASTC 2016 HDD RoadmapWhy are HDD prices tracking SSD prices?  Why don’t they cross over?  These are questions that The SSD Guy is often asked, especially by people who anticipate a crossover in the near future.

In essence it’s because both the HDD industry and the semiconductor industry have set goals for themselves to achieve 30% average annual price reductions.  If they are both on the same trajectory, and if there’s an order of magnitude difference between HDD and SSD prices today, then there will be an order of magnitude difference in the future as well.

The 30% average annual decline in SSD prices has a convenient name: Moore’s Law.  Although there’s no physical, economic, or other restriction behind Moore’s Law (so it’s not really a law at all) it serves as a guide for the industry.  Chip makers set their sights at doubling the number of transistors on a chip every couple of years, and this equates to average annual price decreases of 30%.

The HDD business also Continue reading

IBM Software + SanDisk Hardware

One of SanDisk's InfiniFlash BoardsIn a joint press release, SanDisk and IBM announced support for each other’s products.  The IBM Spectrum Scale filesystem will support SanDisk’s InfiniFlash all-flash array to provide a high-capacity high-speed software-defined storage system.

At first glance this may seem a little odd, since IBM sells its own all-flash array, the FlashSystem, which became an IBM product line when the company acquired Texas Memory Systems (TMS) back in 2012.  That is not the case, though.  IBM has been validating that its Spectrum Storage products will work with just about any storage type that its customers may want to use.  Rather than narrowing this software’s support to only IBM storage systems, IBM is showing that Spectrum Scale is flexible enough to work with a multitude of solutions, supporting InfiniFlash the same as it does other internal server capacity and other external storage in the form of JBODs (“Just a Bunch of Disks”) or JBOFs (“Just a Bunch of Flash”).

In this case IBM has worked with SanDisk to validate that its Spectrum Scale storage management software works with InfiniFlash, just as it does with those many other storage solutions.

In the announcement IBM explains that Continue reading

3D XPoint Memory at the Storage Developer’s Conference

3D XPoint Report GraphicThis Sunday (Sept. 20, 2015) I will be presenting my company’s findings on the 3D XPoint memory that was introduced by Intel and Micron in July.  I will be speaking at the Storage Networking Industry Association (SNIA) Storage Developer Conference (SDC) Pre-Conference Primer.  You can click the name  to be taken to the agenda.

This won’t be the only talk about persistent memory technology at the conference.  Prior to my presentation storage consultants Tom Coughlin and Ed Grochowski will give an overview of advances in nonvolatile memories, and following my presentation will be two Intel talks.

Intel will be covering this new technology a lot during the conference.  Of a total of 120 presentations at the conference and pre-conference primer, Intel will be presenting nine, seven of which directly name persistent memory or nonvolatile memory in the title.  Other firms will also be talking about NVM: AgigA, Calypso, HP, Pure Storage, and SMART Modular.  Even Microsoft alludes to it in a couple of its presentation titles.  Persistent memory is a hot issue.

So, the question for readers of The SSD Guy blog is: “Will this do away with SSDs?”

This is a question that was Continue reading

Comparing DWPD to TBW

TBW-DWPDA couple of specifications for SSD endurance are in common use today: Terabytes Written (TBW) and Drive Writes Per Day (DWPD).  Both are different ways to express the same thing.  It seems that one vendor will specify endurance using TBW, while another will specify DWPD.  How do you compare the two?

First, some definitions.  “Terabytes Written” is the total amount of data that can be written into an SSD before it is likely to fail.  “Drive Writes Per Day” tells how many times you can overwrite the entire capacity of the SSD every single day of its usable life without failure during the warranty period.  Since both of these are guaranteed specifications, then your drive is most likely to last a lot longer than the number given by the SSD’s maker.

To convert between the two you must know the disk’s capacity and the warranty period.  If  drive maker gives you TBW but you want to know DWPD you would approach it Continue reading

Who’s #1 in Flash Arrays?

Jay KramerA recent conversation with some fellow analysts revealed a puzzling set of claims.  EMC, at its EMC World conference (May 3-7) claimed to be the leader in flash array shipments.  The very next week, in the same Las Vegas hotel, IBM also claimed leadership in flash.

Who do you believe?

Well a friend of The SSD Guy, marketing consultant Jay Kramer of Network Storage Advisors Inc., tallied up all of the leadership claims he could find and provided this list:

  • EMC is counting XtremIO Arrays as units shipped and according to Gartner Group held the #1 market share position with a 31.1% share, which is over a ten percentage point share lead
  • IBM is counting capacity of PBs shipped with all of their flash storage solutions: The FlashSystem 840, 900, V840, V9000, DS8000, plus the XIV systems, Storwize V7000, IBM Flash DAS, and IBM PCIe Adapters
  • NetApp is the leader if you count total flash systems shipped (NetApp-branded plus privately-branded systems) spanning multiple years as their SANtricity operating system and E-Series platforms have sold over 750,000 units
  • Pure Storage uses its 700% growth to show that it’s the #1 fastest-growing flash storage company
  • Then, if you want to compare any vendor’s total all flash array (AFA) systems sold this past year against hybrid storage arrays, Nimble Storage beats any of the AFA vendors.

Continue reading

MLC vs. eMLC – What’s the Difference?

eMLCFrom time to time IT managers ask The SSD Guy if there’s an easy way to compare SSDs made with MLC flash against those made using eMLC flash.  Most folks understand that eMLC flash is a less costly alternative to SLC flash, both of which provide longer wear than standard MLC flash, but not everyone realizes that eMLC’s superior endurance comes at the cost of slower write speed.  By writing to the flash more gently the technology can be made to last considerably longer.

So how do you compare the two?  OCZ introduced MLC and eMLC versions of the same SSD this week, and this provides a beautiful opportunity to explore the difference.

As you would expect, the read parameters are all identical.  This stands to reason, since Continue reading

OCZ Comes Roaring Back with NVMe SSD Debut

The OCZ Z-Drive 6000It’s really something to see a company recover from a big challenge, and signs of that happened this week with OCZ’s introduction of a new NVMe-based PCIe SSD they call the Z-Drive 6000 series.

This replacement for the company’s Z-Drive 4000 series is a complete redesign with an obsession for performance.  OCZ tells me that they moved from a 2-hop design to a 1-hop by using the PMC Princeton PCIe SSD controller, and have passed the University of New Hampshire Interoperability Labs’ compliance tests to NVMe 1.1B compliance.

But how does it perform?  Well the 1-hop design helps reduce latency (which is just starting to overshadow IOPS in users’ minds) and the latency of this SSD is significantly lower than competing NVMe SSDs: between 25-30μs, figures that OCZ tells me are very consistent, a big plus for enterprise applications.  As for IOPS, the device can perform under a 70/30 Read/Write load at 330K.

The 6000 series is provided in both standard MLC and eMLC for those who want the security of eMLC and are willing to sacrifice a little performance to sleep better at night.

This product is a good fit for the market needs, and shows how devoted OCZ and its parent Toshiba are to providing high performance in the SSD marketplace.

 

Baidu Goes Beyond SSDs

Baidu's SDF: Software-Defined FlashI have to admit that it’s embarrassing when The SSD Guy misses something important in the world of flash storage, but I only recently learned of a paper that Baidu, China’s leading search engine, presented at the ASPLOS conference a year ago.  The paper details how Baidu changed the way they use flash to gain significant benefits over their original SSD-based systems.

After having deployed 300,000 standard SSDs over the preceding seven years, Baidu engineers looked for ways to achieve higher performance and more efficient use of the flash they were buying.  Their approach was to strip the SSD of all functions that could be better performed by the host server, and to reconfigure the application software and operating system to make the best of flash’s idiosyncrasies.

You can only  do this if you have control of both the system hardware and software.

The result was SDF, or “Software-Defined Flash”, a card that Continue reading