The coming boom in SSD’s

by Robin Harris on Monday, 27 August, 2007

Solid state disks have been around for decades and failed to make the IT mainstream. Why is that about to change?

I did a stint of SSD marketing at DEC in the early 90’s. Then, as now, SSDs offered low I/O latency and high IOPS capacity at an astronomical $/GB.

I’m exceptionally good at making abstract product features meaningful to customers. Everybody says “think outside the box” but few can actually to it.

That’s why so many product benefits sound the same: ROI! CapEx! OpEx! Faster! Eyes glaze over.

Every product has a story to tell and part of marketing’s job is to tell that story well.

But SSDs left me stumped.

I saw three major problems.

  • Cost. People couldn’t get past the $/GB metric. The issues would vary, but the most common was “I can buy a heck of a lot of disks for what you’re asking and take care of performance and capacity at the same time.”
  • Acceptance. As Geoffrey Moore points out, IT directors have a herd mentality. Since so few other people were using them, what was the chance that they should?
  • Need. These folks didn’t know if they needed an SSD and they had no easy way to find out. The fabulous SSD specs couldn’t create a need from unseen problems.

Consumerization of SSDs
IT consumerization is the process by which low-cost and high volume products migrate into IT. We’ve seen it with CPUs, networks, OS’s, I/O busses, disk drives, data bases and applications. Volume rules.

SSDs are next.

Most consumerization works because the volume “consumer” products are about as good as the proprietary products and cost a lot less. Not only to buy, but to engineer because a volume-based infrastructure of development tools, support chips and helpful add-ons develops. These are network effects.

SSDs are going to benefit through another mechanism: consumer education.

Thumb drives as baby SSDs.
The consumer SSD is the flash-based thumb drive. The thumb drive and its close relative, the flash-based notebook disk, knock down 2 of the 3 reasons people haven’t bought into SSDs while helping with the 3rd.

Cost. Notebook SSDs currently cost about $15/GB, while consumer SATA drives are available for ~$0.20/GB. That is a 75x difference, yet consumers are psyched to buy. Why? Because folks now understand that capacity isn’t the important metric when you buy storage.

Flash-based SSDs in high-end notebooks will accelerate the education of the senior execs who buy them. So when an IT director says “I want to buy SSDs for the datacenter” the C-level execs will understand. Not the details, but the concept.

Acceptance. All the high-end sub-notebooks will have SSD options. That means the technology is safe if Apple, Dell, HP and Lenovo are selling it and their friends are buying it.

Need. Consumer SSDs will help datacenter types because for the first time C-level execs will understand emotionally and intellectually that SSDs can make a difference in computer system performance and power use.

But a notebook SSD is imperfectly analogous to a datacenter SSD. For one, it doesn’t replace all existing storage, which means decisions have to be made on what to migrate. Further, the performance implications for servers aren’t widely understood, so the economic benefits are underestimated.

The SSD companies will still have their marketing work cut out for them.

The StorageMojo take
While consumer SSD’s – including USB thumb drives – will provide datacenter SSD vendors a door into the enterprise, it is up to the vendors to walk through it.

After years of playing on the margins of IT SSD vendors face a major cultural shift. They currently sell their products through specialized integrators who target the high performance applications where SSD benefits have been recognized for years by knowledgeable technical customers.

The new SSD markets are horizontal and require new integrators and a new story. Enterprise IT has fundamentally changed in the last 10 years with the advent of network-based services. This has created new opportunities for traditional SSD companies such as Texas Memory Systems and Solid Data while also opening up the market to new approaches such as Gear6.

Engineering-dominated tech firms have a spotty record of success when consumerization hits. Solid state disks will have a major growth spurt over the next five+ years. Will the old-line SSD companies be the ones to take advantage of it?

Comments welcome.

{ 4 comments… read them below or add one }

Marc Farley August 27, 2007 at 8:10 am

Robin, you like to look at power consumption. Large scale SSDs are a lot less green than spinning disks. Maybe not for things the size of iPods, but for disk drive sized SSDs they certainly are. So, they cost more than disk, are slower than disk (if you are thinking flash) and take more power than disk. Three strikes.

desire athow August 28, 2007 at 6:53 am

I wonder whether it would make more sense to have hybrid “best-of-both-worlds” solutions rather than purely SSDs or purely platter based ones. Also, one has to bear in mind that in 5+ years, (it is a long shot, I know), i envision that hard/3D Optical drives will probably have ousted tapes thanks to the fact that manufacturers like Samsung or Seagate will have wholeheartedly embraced SSD, leaving no choice to the consumer.

gm August 28, 2007 at 3:28 pm

New to this blog.. Good blog, first let me say I normally don’t engage blogs but I’ve had way too much coffee and the comments set me off a bit..

SSD has been kicking around for a long time and has been a real ROI winner for applications where low storage IO latency is critical. Right now, we are seeing an explosion in solid state memory technology – manufacturers are designing for vertical applications, including Personal media devices, set-top boxes, the mobile phones, cameras, data center and laptops. Exciting stuff !!!

Today’s bang for the buck for the PC industry is laptops with SSD’s. Fast boot times, power-on data availability, no spin-up required. In comparing SSD to spinning media, disk performance for laptops w/ 5400 rpm drives get about 25 MB/s on a good day. The new flash memory chips read data at about 60-80MB/s with latency of 5uS vs. 180 uS for laptop disks. So, SSD does have the performance capability for laptops and without the disk spin-up time. I can live with that…

Hybrid drives are here to stay for a while, I put a hybrid drive in my HP laptop, its great… As soon as the flash or the next solid state memory technology (Spansion’s products) improves write capabilities and reduces price, its good bye to spinning disk drives on laptops.

There is a rumor that SSD with increased write capabilities will reach price parity with spinning media in 5-7 years. I believe broad adoption of SSD will occur for economic reasons. Consumer products will move to SSD when the costs of SDD out ways the cost of warranty repairs and support calls for spinning disk failures or quality of service related issues (the device stalls due to seek problems).

The enterprise will move to SSD when they examine the costs in lost revenue due to degraded raid performance and when they compare data center costs cause by failed drives. The enterprise has additional facility energy costs related to spinning drives and cooling the data center.

I hope my math is right here..
32 spinning 15K 3.5″ drives (500W) costs about $2500 to run and cool in well designed data center – more $$ in a poorly designed data center. In Japan, it costs about $5000 for the same drives.

Depending on drive capacity (300GB vs 72GB), spinning enterprise drives burn between 43mW and 210mW per GB, costing between $7.10 and $35 per GB annually in energy cost. Drive specs show SATA drives use about 5-15% less power than SAS, fibre channel and scsi. I’m not sure I believe that number. Laptop drives are use about 20mW/GB. Sandisk claims 15mW/GB for their 64GB SATA Flash disk, costing about $2.10 annually in data center energy per GB. Too bad flash has such limited write capabilities.

On the optical front, Optware had already produced a 30GB holographic memory card for $0.90 and InPhase has a 300GB 5.25″ disk, not R/W, but worm drives. The problem with this technology today the drive is over $1000. LOTS, the pioneer in optical “write once” tape closed its doors a few years ago.

I think we have a ways to go before R/W optical media become a reality, not in my life time anyway

Mark Hayashida September 6, 2007 at 7:17 pm

Working for an enterprise SSD vendor, I see a lot of reasons why the market for SSDs is growing: lower prices, greater capacities, market awareness — but the “biggie” is the “need” for SSDs driven by the growth of high transaction rate, real-time applications (e.g. trading and retailing) and, in the telecommunications space, the vast array of service applications for mobile devices.

Robin points out some very valid observations including the unfortunate view that SSDs are just like rotating storage only faster and by just adding more disks can solve their performance problems at a lower price compared to implementing SSDs. Often this is not the case. Here’s just one example of why.

To get lots of IOPs out of a disk farm, the server and software need to be able to develop a large queue. You can visualize this if you assume for a moment a single threaded process asks for random data from a single disk. If the disk has to move its read/write head, the disk’s not going to complete this IO for 5 to 10 milliseconds. This is eons in processor time and would limit the system to about 100 to 200 IOs per second. So in order to get thousands of IOPS (aggregated) you clearly need many spindles. But more importantly, the server and the app also need to be able to generate the additional, simultaneous parallel processes or threads (the queue), each of which will remain open for the 5 to 10 milliseconds. Hence the server’s queue capacity and the software’s ability to generate parallel requests are integral in getting high IO rates when using disk arrays. In normal operation there may be hundreds or thousands of open processes waiting for service by the disk farm.

With SSDs this is not the case. Even a single thread or process will get serviced in microseconds, so potentially, 10’s of ‘000s of IOPS can be achieved with little or no queue in the server.

There are many benefits to this.

Fewer, Cheaper Servers with lower system power consumption — some of which is due to lower server consumption, some due to the lower consumption of the SSD. You also get lower licensing and administration costs, less tuning and less issue with fragmentation, but often the biggest cost saving is in server stability and preventing server performance spikes or worse case, crashes. This is not an intuitive benefit of SSDs unless you examine the queue issue.

With a disk farm under a high transaction load we’ve established that you have a big queue. This uses lots of server resources and because of the long delays of the drives, any large burst of requests will initially get staged in the server which can increase the queue beyond the server capacity causing instabilities or a crash.

With SSDs, IOPs are handled synchronously and at about the same speed as the network or server can supply them, so crashes due to requests backing up in the server are eliminated.

This example points out the need to analyze the costs of SSDs in conjunction with the rest of the system. Only then can the significant benefits be measured against the higher costs per byte.

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