rayo 3 by El Garza (cc) (from Flickr)

Although technically Project Lightening and Thunder represent some interesting offshoots of EMC software, hardware and system prowess,  I wonder why they would decide to go after this particular market space.

There are plenty of alternative offerings in the PCIe NAND memory card space.  Moreover, the PCIe card caching functionality, while interesting is not that hard to replicate and such software capability is not a serious barrier of entry for HP, IBM, NetApp and many, many others.  And the margins cannot be that great.

So why get into this low margin business?

I can see a couple of reasons why EMC might want to do this.

• Believing in the commoditization of storage performance.  I have had this debate with a number of analysts over the years but there remain many out there that firmly believe that storage performance will become a commodity sooner, rather than later.  By entering the PCIe NAND card IO buffer space, EMC can create a beachhead in this movement that helps them build market awareness, higher manufacturing volumes, and support expertise.  As such, when the inevitable happens and high margins for enterprise storage start to deteriorate, EMC will be able to capitalize on this hard won, operational effectiveness.
• Moving up the IO stack.  From an applications IO request to the disk device that actually services it is a long journey with multiple places to make money.  Currently, EMC has a significant share of everything that happens after the fabric switch whether it is FC,  iSCSI, NFS or CIFS.  What they don’t have is a significant share in the switch infrastructure or anywhere on the other (host side) of that interface stack.  Yes they have Avamar, Networker, Documentum, and other software that help manage, secure and protect IO activity together with other significant investments in RSA and VMware.   But these represent adjacent market spaces rather than primary IO stack endeavors.  Lightening represents a hybrid software/hardware solution that moves EMC up the IO stack to inside the server.  As such, it represents yet another opportunity to profit from all the IO going on in the data center.
• Making big data more effective.  The fact that Hadoop doesn’t really need or use high end storage has not been lost to most storage vendors.  With Lightening, EMC has a storage enhancement offering that can readily improve  Hadoop cluster processing.  Something like Lightening’s caching software could easily be tailored to enhance HDFS file access mode and thus, speed up cluster processing.  If Hadoop and big data are to be the next big consumer of storage, then speeding cluster processing will certainly help and profiting by doing this only makes sense.
• Believing that SSDs will transform storage. To many of us the age of disks is waning.  SSDs, in some form or another, will be the underlying technology for the next age of storage.  The densities, performance and energy efficiency of current NAND based SSD technology are commendable but they will only get better over time.  The capabilities brought about by such technology will certainly transform the storage industry as we know it, if they haven’t already.  But where SSD technology actually emerges is still being played out in the market place.  Many believe that when industry transitions like this happen it’s best to be engaged everywhere change is likely to happen, hoping that at least some of them will succeed. Perhaps PCIe SSD cards may not take over all server IO activity but if it does, not being there or being late will certainly hurt a company’s chances to profit from it.

There may be more reasons I missed here but these seem to be the main ones.  Of the above, I think the last one, SSD rules the next transition is most important to EMC.

They have been successful in the past during other industry transitions.  If anything they have shown similar indications with their acquisitions by buying into transitions if they don’t own them, witness Data Domain, RSA, and VMware.  So I suspect the view in EMC is that doubling down on SSDs will enable them to ride out the next storm and be in a profitable place for the next change, whatever that might be.

And following lightening, Project Thunder

Similarly, Project Thunder seems to represent EMC doubling their bet yet again on the SSDs.  Just about every month I talk to another storage startup coming out in the market providing another new take on storage using every form of SSD imaginable.

However, Project Thunder as envisioned today is not storage, but rather some form of external shared memory.  I have heard this before, in the IBM mainframe space about 15-20 years ago.  At that time shared external memory was going to handle all mainframe IO processing and the only storage left was going to be bulk archive or migration storage – a big threat to the non-IBM mainframe storage vendors at the time.

One problem then was that the shared DRAM memory of the time was way more expensive than sophisticated disk storage and the price wasn’t coming down fast enough to counteract increased demand.  The other problem was making shared memory work with all the existing mainframe applications was not easy.  IBM at least had control over the OS, HW and most of the larger applications at the time.  Yet they still struggled to make it usable and effective, probably some lesson here for EMC.

Fast forward 20 years and NAND based SSDs are the right hardware technology to make  inexpensive shared memory happen.  In addition, the road map for NAND and other SSD technologies looks poised to continue the capacity increase and price reductions necessary to compete effectively with disk in the long run.

However, the challenges then and now seem as much to do with software that makes shared external memory universally effective as with the hardware technology to implement it.  Providing a new storage tier in Linux, Windows and/or VMware is easier said than done. Most recent successes have usually been offshoots of SCSI (iSCSI, FCoE, etc).  Nevertheless, if it was good for mainframes then, it certainly good for Linux, Windows and VMware today.

And that seems to be where Thunder is heading, I think.

Comments?

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Post tags: commoditization of storage performance, Commodity hardware, EMC, EMC Project Lightening, EMC Project Thunder, external shared memory, Linux, NAND, SSD, VMware, Windows

Prison Planet by AZRainman (cc) (from Flickr)

[Long post] Read another intriguing post by David Vellente at Wikibon today about the emergence of IT shops becoming service organizations to their industries using the cloud to hosting these services.  I am not in complete agreement with Dave but he certainly describes a convincing picture.

His main points are:

• Cloud storage and cloud computing are emerging as a favorite platform for IT-as-a-service.
• Specialization and economics of scale will generate an IT-as-a-service capability for any organization’s information processing needs.

I would have to say another tenet of his overall discussion is that IT matters, a lot and I couldn’t agree more.

Cloud reality

For some reason I have been talking a lot about cloud storage this past couple of weeks, in multiple distinct venues.  On the one hand, I was talking with a VAR the other day and they were extremely excited about the opportunity in cloud storage. It seems getting SMB customers to sign up for a slice of storage is easy and once they have that, getting them to use more becomes a habit they can’t get rid of.

I thought maybe the enterprise level would be immune to such inducements, but no.  Another cloud storage gateway vendor,  StorSimple, I talked with recently was touting the great success they were having displacing tier 2 storage in the enterprise.

Lately, I heard that some small businesses/startups have decided to abandon their own IT infrastructure altogether and depend entirely on cloud offerings from Amazon, RackSpace and others for all they need.  They argue that such infrastructure, for all its current faults, will have less downtime than anything they could create on their own within a limited budget.

So, cloud seems to be taking off, everywhere I look.

Vertical support for IT as a service

Dave mentions plenty in his lengthy post that a number of sophisticated IT organizations are taking their internal services and becoming IT-as-a-service profit centers.  Yes, hard to disagree with this one as well.

But, it’s not the end of IT organizations

However, where I disagree with Dave is that he sees this as a winning solution, taking over all internal IT activities.  In his view, either your IT group becomes an external service profit center or it’s destined to be replaced by someone else’s service offering(s).

I don’t believe this. To say that IT as a service will displace 50+ years of technology development in the enterprise is just overstatement.

Dave talks about WINTEL, displacing mainframes as the two monopolies created in IT.  But the fact remains, WINTEL has not eliminated mainframes.  Mainframes still exist and arguably, today are still expanding through out the world.

Dave states that the introduction of WINTEL reduced the switching cost of mainframes, and that the internet and the cloud that follows, have reduced the costs yet again. I agree.  But, that doesn’t mean that switching cost is 0.

Ask anyone whether SalesForce.com switching cost inhibits them from changing services and more than likely they will say yes.  Switching costs have come down, but they are still a viable barrier to change.

Cloud computing and storage generates similar switching costs not to mention the time it takes to transfer TBs of data over a WAN.  Whether a cloud service uses AWS interface, OpenStack, Azzure or any of the other REST/SOAP cloud storage/cloud computing protocols is a formidable barrier to change.  It would be great if OpenStack were to take over but it hasn’t yet, and most likely won’t in the long run.  Mainly because the entrenched suppliers don’t want to help their competition.

IT matters, a lot to my organization

What I see happening is not that much different from what Dave sees, it’s only a matter of degree.  Some IT shops will become service organizations to their vertical but there will remain a large proportion of IT shops that see

• That their technology is a differentiator.
• That their technology is not something they want their competition using.
• That their technology is too important to their corporate advantage to sell to others.

How much of this is reality vs. fiction is another matter.

Nonetheless, I firmly believe that a majority of IT shops that exist today will not convert to using IT as a service.   Some of this is due to sunk costs but a lot will be due to the belief that they are truly better than the service.

That’s not to say that new organizations, just starting out might be more interested in utilizing IT as a service.  For these entities, service offerings are going to be an appealing alternative.

However, a small portion of these startups may just as likely conclude that they can do better or believe it’s more important for them to develop their own IT services to help them get ahead.  Similarly, how much of this is make believe is TBD.

In the end, I believe IT as a service will take it’s place alongside IT developed services and IT outsourced development as yet another capability that any company can deploy to provide information processing for their organization.

The real problem

In my view, the real problem with IT developed services today is development disease.  Most organizations, would like increased functionality, and want it ASAP but they just can’t develop working functionality fast enough.  I call slow functionality development, missing critical features with lots of bugs development disease.  And it’s everywhere today and has never really gone away.

Some of this is due to poor IT infrastructure, some is due to the inability to use new development frameworks, and some of it is due to a lack of skills.  If IT had some pill they could take to help them develop business processing faster, consuming less resources with much fewer bugs and fuller functionality, they would never consider IT as a service.

That’s where the new frameworks of Ruby on Rails, SpringForce and the like are exciting. Their promise is providing faster functionality with fewer failures. When that happens, organizations will move away from IT as a service in droves, and back to internally developed capabilities.

But, we’re not there yet.

—-

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Post tags: Cloud computing, Cloud Storage, Cloud storage gateways, Development disease, Development frameworks, IT internal development, IT-as-a-service

Untitled by johnwilson1969

We have been discussing off and on how smart power meters (see Smart metering data storage appetite) and intelligent sensors (see the Sensor cloud comes home) such as smart thermostats generate copious amounts of data.  Sensors and meters such as these are used in a new power distribution network called the smart grid.

But recently there was a report in Technology Review of how smart thermostats can “communicate” with power companies to determine current energy costs and then alter temperature settings to reduce power use.

Power companies give discounts to those customers who install the smart thermostats in the hope that such devices will lower peak power use.  If this happens they will save significant investments in new power generation and power lines to satisfy the ever-growing peak power level. This probably works best in summer with A/C equipment which is a prime user of electricity during peak consumption periods. The story goes on to say that these smart thermostats have been used in a small test bed but are about to be rolled out on a wider basis.

Power thrashing?!

One serious concern brought up in the article is that when such devices are rolled out on a large scale there is a high chance of power thrashing.

As smart thermostats reduce home power consumption in volume, they may end up driving the cost of power down low enough such that the thermostats, on the next cycle, will start to consume more power, leading to power thrashing.

If this happens on a big enough region, such oscillations of power use may lead to an even higher peak than what was in place prior to the smart grid.  And if the thermostats have been in place for a while and succeeded in reducing peak power capabilities, such thrashing may lead to a smart grid crash or congestion collapse.

Thrashing prevention on the power grid

There are three ways to prevent power thrashing:

• Increase the amount of peak power to handle the worst case regional energy working set.
• Decrease the power consumption of the largest power users.
• Decrease the number of consumers.

It would seem the first solution defeats the purpose of the smarter grid.  I believe the second approach can best be implemented by having even more smart appliances which can reduce power consumption on demand.  As for the third approach, this may be infeasible, as you cannot just drop power to consumers without some serious consequences.

Dumb grid solutions

We have for a couple of years now received a discount on our power bill by having a special device attached to our A/C unit that reduces our power consumption on one day a year. It’s not quite as intelligent as the smart thermostats discussed above but it does the job (at least once/year).  Such devices, used on a large scale could provide the capabilities of the smart thermostat but eliminate the potential for thrashing and large power oscillations.

—-

So the smart grid is coming but the smarter it gets the more care we need to take in implementing it.

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Post tags: dumb grid, Peek power, power thrashing, power thrashing prevention, smart grid, smart power systems, smart thermostats

Functional Fusion? by Cain Novocaine (cc) (from Flickr)

One can only be perplexed by the seemingly overwelming adoption of server virtualization and contrast that with the ho-hum, almost underwelming adoption of storage virtualization.  Why is there this significant a difference?

I think the problem is partly due to the lack of an common understanding of storage performance utilization.

Why server virtualization succeeded

One significant driver of server virtualization is the precipitous drop in server utilization that occurred over the last decade when running single applications on a physical server.  It was nothing to see real processor utilization of less than 10% and consequently it was easy to envision that executing 5-10 applications on the single server. And what’s more each new generation of server kept getting more powerful, handling double the MIPs every 18 months or so driven by Moore’s law.

The other factor was that application workloads weren’t increasing that much. Yes new applications would come online but they seldom consumed an inordinate amount of MIPs and were often similar to what was already present. So application processing growth while not flatlining, was expanding at a relatively slow speed.

Why storage virtualization has failed

Data on the other hand continues its never ending exponential growth. Doubling every 3-5 years or less. And the fact that you have more data, almost always requires more storage hardware to support the IOPs being required to support it.

In the past the storage IOP rates was intrinsically tied to the number of disk heads available to service the load.  Although disk performance grew it wasn’t doubling every 18 months, and real per disk performance was actually going down over time, measured as the amount of IOPS per GB.

This drove proliferation of disk spindles and as such, storage subsystems in the data center. Storage virtualization couldn’t reduce the number of spindles required to support the workload.

Thus, if you look at storage performance from the perspective of % IOPS one could support per disk, most  sophisticated systems were running anywhere from 75% to 150% (based on DRAM caching).

Paradigm shift ahead

But SSDs can change this dynamic considerably.  A typical SSD can sustain 10-100K IOPs and there is some liklihood that this will increase with each generation that comes out but the application requirements will not increase as fast.  Hence, , there is a high liklihood that normal data center utilisation of SSD storage perfomance will start to drop below 50% or more, when that happens. -torage virtualization may start to make a lot more sense.

Maybe when (SSD) data storage starts moving more in line with Moore’s law, storage virtualization will become a more dominant paradigm for data center storage use.

—

Any bets on who the VMware of storage virtualization will be?

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Post tags: performance utilization, processor utilization, storage virtualization adoption rate

A head assembly on a Seagate disk drive by Robert Scoble (cc) (from flickr)

An interesting guest post on Claus’s Blog (Claus Mikkelsen of HDS) by Ian Vogelesang of HGST provided some technical/economic insights on why specific disk drives are more economically feasible than others.

It’s a bit hard going and more technical than a typical blog post, but it certainly makes a number of interesting points.

1. There is an interaction between recording density, performance and $/GB when introducing a new, smaller form factor.  Most often drive vendors are trying to maximize GB per drive while IO performance is not as much of a concern.  So they most often try to first come out with their densest drive they can in any new form factor.  I think this is what we have seen with the SFF disks today, i.e., most vendors came out with 10Krpm drives, leaving their faster drives to the LFF.  As recording density for a new technology continues to improve, GB/drive is no longer the driving factor which is when performance rises to the top. At that point then we see the introduction of higher speed drives in a form factor.
2. Enterprise SATA drives perform worse than equivalent capacity SAS drives. In HDS’s case there are two reasons for this: 1) For enterprise storage they append ECC plus other LBA integrity checks to each 512 byte block however, SATA doesn’t support anything but 2**n block size, thus multiple IOs are required to read/validate a block and 2) SAS hardware supports a larger tag command queue than SATA and thus, a better optimized IO queue for multiple IO requests.
3. Global access density requirements are 600IOPs/TB of storage. This is stated as a matter of fact in the post without any background information but is another key factor driving disk changes.

I would love to know more about that last point 600 IOPS/TB. But there wasn’t much else there.  (It seem to me this should have changed over time. It’s certainly worthy of a research study if anybody’s listening out there.)

Shingled writes

One other thing I found interesting is a few statements at the end regarding emerging disk recording technology.  It seems thermally assisted recording (TAR) is not coming along as fast as everyone in the industry thought it would.  As such, the disk industry is considering moving to shingled writes (see my post Sequential Only Disk) which may cause them to abandon random writes.

But there is another solution to non-random writes besides sequential only disk and that is implementing a log structured file for blocks on the disk.  Similar to NetApp’s Data ONTAP, where the system supports random writes but actually writes data on disk drives sequentially.

This requires more smarts in the drive controller but it’s nothing like what’s in SSDs today for wear leveling and is a viable alternative.  The nice thing about a log structured file on disk, is that there is no need to change any IO drivers as the disk drive continues to support random writes (from the server/storage system perspective) but the drives write sequential on the platter.

I would suspect most drive vendors considering shingled writes are busily working on doing something similar to this and it wouldn’t surprise me to see the next generation disks support shingled writes using an onboard log structured file.

What this will do for read sequential IO is another question entirely.

Luckily, data that is read sequentially is often written sequentially and even with a log structured file layout on disk, will more than likely be positioned close together on a disk platter.

—-

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Post tags: disk form factor, disk technology, disk trends, high performance disks, IOPS/TB, log structured file, random writes, recording density, recording technology, RW heads, shingled writes, TAR, thermally assisted recording

Gold Nanowire Array by lacomj (cc) (from Flickr)

A post by Chris M. Evans, in his The Storage Architect blog (Intel inside storage arrays) re-invigorated the discussion we had last year on commodity hardware always loses.

But buried in the comments was one from Michael Hay (HDS) which pointed to another blog post by Andrew Huang in his bunnie’s blog (Why the best days of open hardware are ahead) where he has an almost brillant discussion on how Moore’s law will eventually peter out (~5nm) and as such, will take much longer to double transistor density.  At that time, hardware customization (by small companies/startups) will once again, come to the forefront in new technology development.

Custom hardware, here now and the foreseeable future

Although it would be hard to argue against Andrew’s point nevertheless, I firmly believe there is still plenty of opportunity today to customize hardware that brings true value to the market.   The fact is that Moore’s law doesn’t mean that hardware customization cannot still be worthwhile.

Hitachi’s VSP (see Hitachi’s VSP vs. VMAX) is a fine example of the use of both custom ASICs, FPGAs (I believe) and standard off the shelf hardware.   HP’s 3PAR  is another example,  they couldn’t have their speedy mesh architecture without custom hardware.

But will anyone be around that can do custom chip design?

Nigel Poulton commented on Chris’s post that with custom hardware seemingly going away, the infrastructure, training and people will no longer be around to support any re-invigorated custom hardware movement.

I disagree.  Intel, IBM, Samsung, and many others large companies still maintain an active electronics engineering team/chip design capability, any of which are capable of creating state of the art ASICs.  These capabilities are what make Moore’s law a reality and will not go away over the long run (the next 20-30 years).

The fact that these competencies are locked up in very large organizations doesn’t mean it cannot be used by small companies/startups as well.  It probably does mean that these wherewithal may cost more. But the market place will deal with that in the long run, that is if the need continues to exist.

But do we still need custom hardware?

Custom hardware creates capabilities that magnify Moore’s law processing capabilities to do things that standard, off the shelf hardware cannot.  The main problem with Moore’s law from a custom hardware perspective is it takes functionality that once took custom hardware yesterday (or 18 months ago) and makes it available on off the shelf components with custom software today.

This dynamic just means that custom hardware needs to keep moving, providing ever more user benefits and functionality to remain viable.  When custom hardware cannot provide any real benefit over standard off the shelf components – that’s when it will die.

Andrew talks about the time it takes to develop custom ASICs and the fact that by the time you have one ready, a new standard chip has come out which doubles processor capabilities. Yes custom ASICs take time to develop, but FPGAs can be created and deployed in much less time. FPGA’s, like custom ASICs, also take advantage of Moore’s law with increased transistor density every 18 months. Yes, FPGAs  may be run slower than custom ASICs, but what it lacks in processing power, it makes up in time to market.

Custom hardware has a bright future as far as I can see.

—–

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Post tags: Bunnie's Blog, chip design, Chris M. Evans, Commodity hardware, Custom ASICs, custom hardware, electronic engineering, FPGAs

1918 Farm Auction by dok1 (cc) (from Flickr)

I have had this conversation before (and have blogged about it with Crowdsourcing business analyst …) where there is lots of time and effort (person years?) devoted to scheduling one-on-one meetings between analyst firms and corporate executives. I may be repeating my earlier post but the problem persists and I see an obvious easier way to solve this.

Auction off 1 on 1 time slots

By doing this the company puts the burden on the analyst community by giving every  firm some amount of “analyst buck”s (A$) and then auction off executive meeting slots. In this way the crowd of analysts would determine who best to meet with whom (putting crowdsourcing to work).

Consider today’s solution:

• Send out a list of topics to be discussed at the meeting,
• Have the analyst firm select their top 3 or 5 topics, and
• Have analyst relation’s sift the requests and executive availability to schedule the meetings.

For analyst events with 100s of analyst firms, 20 or more executives, and 10 or more time slots, the scheduling activity can become quite complex and time consuming.

I understand a corporation’s need to make the most effective use of analysts and executive management time, but what better way to make this determination than to let the (analyst) market decide.

How an executive 1 on 1 auction could work

The way I see it is to hold some sort of dutch or japanese auction (see wikipedia auction) where all the analyst firm representatives attended a webex session and bid for 1-1 time slots with various executives. In this fashion the company could have the whole schedule laid out in a single day with the only effort involved in identifying executives, time slots and supplying A$s to analyst firms.

It doesn’t even need to be that sophisticated and potentially could be done on eBay with real money supplied by the company (useable only for bidding in executive time slot auctions) and donated to charity when the process is finished.  There are any number of ways to do this on the quick and cheap.  However, using eBay may be a bit too public but doing this over a conference call with webex would probably suffice just as well and could be totally private.

Of course with this approach, the company may find that their are some executives that are in higher demand than others.  If such is the case, perhaps a secondary auction could be supplied with more time slots. Ditto for executives that have time slots that are not in demand – they could be released from providing time for 1 on 1 meetings.

In my prior post I mentioned the option that maybe the corporation might want more control over who meets who. In that case allocating some A$s to the corporate executives (or A/R as their proxy) to use to augment analyst firm bids might do the trick. Of course providing those firms more A$s would also give them preferential access. Obviously, this wouldn’t provide as much absolute control as spending person years of effort doing 1 on 1 scheduling but it would provide a quick and relatively easy solution to the problem from both the analyst firm as well as analyst relations.

But how much to grant to each analyst firm?

The critical question is the amount of A$’s to provide each firm.  This might take some thought but there is an easy solution. Just use last years analyst spend as the amount of A$s to provide the firm.  Another option is to provide some base level of analyst bucks to any firm invited to attend and then add more for the prior year spend.

Possibly, a less appealing approach (to me at least) is to give each analyst firm an amount proportional to their annual revenue regardless of company spending with the firm.  But perhaps some combination of the above, say

1/3 base amount for any invitee + 1/3 proportional to annual spend +1/3 proportional to annual firm revenue = A$s

would work.

In my previous post I suggested so many A$s per analyst. As such, bigger firms with more analysts would get more than firms with less analysts. But I feel the formula described above makes more sense to me.

Information provided to facilitate the 1 on 1′s auction

In order for the auction to work well, analyst firms would need to know more information about the executive whose time is being auctioned off.  But aside from that just a schedule of the time slots available would allow the auction to work. On the other hand, some idea of the company’s org chart and where the executive fit in would be very useful to facilitate the auction.

—-

That’s it, pretty simple, set up a conference call, send out executive information and org chart, allocate analyst bucks and let the bidding begin.

Auctioning off Lot-132: 30 minutes of Ray Lucchesi’s time …, let the bidding begin.

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Post tags: analyst bucks, analyst meetings, analyst relations, meeting auctions

Toshiba's 2.5" SSD (from SSD.Toshiba.com)

Had a talk the other week with an storage executive about SSD and NAND cost trends.  It seemed that everyone thought that $/GB for SSD was going to overtake (be less costly) than enterprise class disk sometime in 2013.  But it appeared that NAND costs weren’t coming down as fast as anticipated and now this was going to take longer than expected.

A couple of other things are going on in the enterprise disk market that are also having an effect on the relative advantage of SSDs over disks.  Probably, most concerning to SSD market is enterprise storage’s new penchant for sub-LUN tiering.

Automated sub-LUN storage tiering

The major storage vendors all currently support some form of automated storage tiering for SSD storage (NetApp’s Flash Cache does this differently but the impact on NAND storage requirements is arguably similar).  Presumably, such tiering should take better advantage of any amount of SSD/NAND storage available to a storage system.

Prior to automated sub-LUN storage tiering, one had to move a whole LUN to SSDs to take advantage of its speed. However, I/O requests or access are not necessarily at the same intensity for all blocks of a LUN.  So one would typically end up with an SSD LUN with a relatively few blocks being heavily accessed while the vast majority of its blocks would not be being hit that much.  We paid the high price of SSD LUNs gladly to get the high performance for those few blocks that really needed it.

However, with sub-LUN tiering or NAND caching, one no longer has to move all the blocks of a LUN into NAND storage to gain its benefits.  One can now just have the system identify those select blocks which need high performance and move those blocks and those blocks only to NAND storage.  The net impact of sub-LUN tiering or NAND caching is that one should require less overall NAND storage to obtain the same performance as one had previously with SSDs alone.

On the other hand, some would say that making the performance advantages of NAND be available at a lower overall cost might actually increase the overall amount of NAND shipments. Also with automated sub-LUN tiering in place, this removes all the complexity needed previously to identify which LUNs needed higher performance.  Reducing such complexity should increase SSD or NAND market penetration.

Nonetheless, I feel that given todays price differential of SSDs over enterprise disk, the people buying SSDs today have a very defined need for speed and would have paid the price anyways for SSD storage.  Anything we do to make satisfying that need with less SSD or NAND storage should reduce the amount of SSDs shipped today.

But getting back to that price crossover point, as the relative price of NAND on $/GB comes down, having an easy way to take advantage of  its better performance should increase its market adoption, even faster than price would do alone.

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Post tags: SSD disk crossover, SSD market dynamics