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What will be the Flavor of the 2011 SSD Market?
Editor:- December 20, 2010 - if you'd like to see a preview of SSD news in 2011 - I've started my - List of 11 SSD market predictions for 2011 - in the SSD Buyers Guide.

In past years these SSD market predictions have accurately anticipated the tone of market twists and shifts.

How about other types of storage? If you're new to the storage market - or just want to review what's been happening in recent weeks and months - a good starting point is storage history - which includes archived news going back 10 years - with the main news story for each week being the link to that week's news. And the history page goes back much further than that - including milestones from my 20 years of publishing storage buyers guides.
click here for storage market research directory For those looking for market reports, numbers and other educated guesses and analysis - see the companies listed on the storage market research and analysts directory.
why does Lone Star SSD pioneer
still favor Single Level Cell?
Editor:- December 16, 2010 - I recently interviewed Jamon Bowen, Director of Sales Engineering for Texas Memory Systems and asked him about the use of SSDs in financial applications like banks and derivatives traders.

I started by saying that among enterprise SSD makers - TMS now seems like one of the few companies which doesn't include MLC in their server SSD product line.

Leading the MLC enterprise tide - Fusion-io has been pushing its MLC based PCIe SSDs into server apps since 2007. And and since 2009 SandForce has been offering its SSD oem partners (now numbering over 20 companies) an easy to integrate controller technology which manages data integrity and endurance to a degree which enables intensive write IOPS SSDs using MLC - to last for 5 years. And more recently - in September 2010 - a year after shipping its first enterprise SLC only SAS SSDs - Pliant Technology reacted to market demand and started offering customers MLC variants.

So I asked Jamon Bowen - what's going on? What's TMS policy about MLC SSDs?

Bowen said I was right in thinking that the company doesn't ship any MLC SSDs. Its market is at the high end of the SSD performance range. As a company - he said TMS has evaluated and used more types of memory technology than anyone else in the market. And they have also evaluated consumer grade MLC.

He mentioned several related reasons for not using MLC right now in their SSD products.

He said current consumer grade MLC nand flash has endurance on the order of 3,000 write cycles. Although it would be possible for TMS to design an ASIC controller with heavy use of over provisioning and parallelism (which would cut down the average latency and extend SSD life) the cost of doing this - at the high end of the performance spectrum (and in the legacy SSD market where the flash management is transparently offloaded from the host) - would nibble away at the native cost advantages of the cheaper MLC. He said the end result would be a rackmount MLC SSD that was only 50% cheaper than using SLC. And another problem would be that the company's burn-in process (done for QA as part of manufacturing) would use up 10% of the endurance life before the SSD even reached the customer.

Bowen said that new types of so called "enterprise MLC flash" - which use enhanced cell programming circuitry in the chip design - might shift the balance of the viability equation. He said that customers would not see consumer grade MLC based SSDs from TMS in the next couple of years. On the other hand he said that TMS is interested in eMLC and its engineering team can move quickly to bring products to the market.

I said I was surprised by how popular - articles about flash endurance - had become with the readers of - considering that readers have to get engaged with semiconductor and architectural complexities to follow the arguments.

Jamon Bowen said if users were fixated too much on wear out - they might not realize that other factors in SSD design could contribute just as much or more to SSD failure.

On the subject of SSD technology education - in a follow up email Jamon Bowen suggested - "It might be a worthwhile endeavor to start educating the reader base on the difference between eMLC and MLC as I expect that across the market vendors will be highlighting eMLC vs MLC in a similar way that SLC and MLC are compared today."
click for RAM SSDs page In another part of this interview I learned some surprising things about the state of the RAM SSD market - including the fact that in some applications they are cheaper than flash. to read the article
Fusion-io discusses MLC SSDs in banks
Editor:- December 7, 2010 - Fusion-io today announced that it has been working closely with Credit Suisse to integrate ioMemory SSDs with its Advanced Execution Services trading platform to improve its data access performance, maximizing the effectiveness of its low latency trading platform architectures.

Editor's comments:- trading banks using SSDs isn't new. So my initial inclination was to ignore this news story. But I'm glad I didn't - because I learned a lot when I spoke to Fusion-io's CEO David Flynn yesterday.

I asked David Flynn - what's your feedback from banks and financial customers about the issue of MLC versus SLC (SSDs) in their critical financial apps. Is it something which they say they have concerns about?

David Flynn's answers surprised me and I hope you find them interesting too.

Re MLC vs SLC concerns in Fusion-io's financial customer base...

David said that their customers don't raise this as a concern. Over 80% of the SSDs that Fusion-io has sold in the last couple of years have been MLC rather than SLC - and he thinks that they probably have a bigger base of enterprise MLC SSDs which has been operating longer in customer sites (upto 3 years) than any other company.

David Flynn said that while MLC poses technical challenges Fusion-io's flash management architecture (some of which I have written about before) provides high data integrity. For example - their SSDs don't lose any data even if entire flash chips fail. That in itself isn't unique - but something new to me was learning that their SSDs do data healing (just like some of the high end RAM SSDs).

He said that - in additional to real-time data integrity checks - their SSDs do a weekly background read, verify, fix and rewrite of the entire flash array to prevent bit rot. (Data can get corrupted in seldom used flash blocks due to charge leakage as well as disturb errors due to other write activities in the same chip. The data healing process ensures that users don't have to over rely on the long term data retention characteristics of the raw flash.)

I asked David Flynn what his view was about data recovery of flash SSDs. He confirmed my guess that most enterprise customers don't need it - because they're doing backups. He also said he didn't recall any cases where their own SSDs had suffered from endurance related burnout.

While on this subject we talked about the advantage of SSD accelerated backup. He said that a general problem for high work load customers using just hard disk storage was that they couldn't extract data in real-time to do backups because their user application performance would suffer.
click here to see collected articles about SSD reliability David Flynn said that a beneficial side effect for many customers who used their SSDs was that they could do backups about 6x faster and for many customers it was viable to do backups while their servers were at peak user loads.
what's inside the SSD? readers want to know even more!
Editor:- December 6, 2010 - recently listed the top 20 SSD articles (viewed by readers in November) on the market research page.

Pageviews of the classic SSD endurance article grew 48% year on year - making it the #1 most popular article for the 1st time - and dislodging the previous encumbant SSD Buyers Guide.

Reader interest in the nuances of technologies inside SSDs is indicated by the upward creep of the SSD controller page in this list...
click here for storage market research directory ...and also by the sustained strong interest in MLC, SLC and RAM memory issues and how they affect SSD performance, price and reliability. ...see the market research page
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WhipTail logo - click for company profile click to see more SSD  Bookmarks
SSD Bookmarks series

suggestions by

- James Candelaria, CTO - WhipTail Tech
Here's an article written by or about WhipTail Tech

GlassHouse Technologies VMworld interview with James Candelaria, CTO, WhipTail - (video on YouTube)

James Candelaria says he chose this video because, "Virtual Desktop Initiative (VDI) is the most I/O intensive workload for storage. Without a proven solid-state shared storage option to deliver performance and reduce the overall storage TCO of VDI, this huge opportunity will simply never get off the ground."

Other SSD article suggestions...

Understanding how storage design has a big impact on your VDI - by blogger Brian Madden

James Candelaria says he recommends this article because, "Although we feel this article underestimates the true I/O demand of each desktop, overall it does a great job of explaining VDI's "dirty little secret" of not only how many IOPs are needed to scale a VDI deployment, but also how the majority of the workload is write-intensive."

Consider compression for primary storage optimization - by Jeff Boles and Jeff Byrne (Taneja Group) - published on InfoStor

James Candelaria says he recommends this article because, "This article clearly articulates the pros and cons of traditional approaches to data deduplication and compression options for primary storage and illustrates the achievement of being able to leverage SSD to overcome all challenges to offer this benefit inline/inband."

Editor:- thanks James for sharing your SSD links.

see also:- WhipTail - editor mentions on
SSD Data Recovery Concepts & Methodologies
It's hard enough understanding the design of any single SSD. And there are so many different designs in the market.

Have you ever wondered what it looks like at the other end of the SSD supply chain - when a user has a damaged SSD which contains priceless data with no usable backup?
broken barrel image - click to read this data recovery article If so - this article - written by Jeremy Brock, President, A+ Perfect Computers - who is one of a rare new breed of SSD recovery experts will give you some idea. read the article
What's the best / cheapest - PC SSD?
Editor:- I often get emails from readers which ask the above question.

An article on - called What's the best / cheapest PC SSD? - is my attempt to create a simple FAQs page - which answers the question...
click to read this article ...of why I can't answer your question - and follows on to pose some probing questions which you can ask yourself. the article
SSDs - computer tonic medicine?
The risk of flash SSD wear-out due to ineffective endurance control is like that of influenza.

Just because you've already had it before - or been innoculated against the previous strain doesn't mean you are invulnerable to what may happen in the next flash / flu pandemic.
image shows the mouse wizard Spellabyte stirring the potion - click to read SSD tonic article A good way to think about SSDs is like vitamin supplements or medicine for computers. the article
Fast Purge SSDs when "Rugged" won't do
The need for fast and secure data erase - in which vital parts of a flash SSD or its data are destroyed in seconds - has always been a requirement in military projects.
Fast Purge flash SSDs directory & articles Although many industrial SSD vendors offer products with extended "rugged" operating environment capabilities - and even notebooks SSDs come with encryption - it's the availability of fast data purge which differentiates "truly secure" SSDs which can be deployed in sensitive applications.
this way to the Petabyte SSD
In 2016 there will be just 3 types of SSD in the datacenter.

One of them doesn't exist yet - the bulk storage SSD.

It will replace the last remaining strongholds of hard drives in the datacenter due to its unique combination of characteristics, low running costs and operational advantages.
click to read the article -  reaching for the petabyte SSD - not as scary as you may think ... The new model of the datacenter - how we get from here to there - and the technical problems which will need to be solved - are just some of the ideas explored in this visionary article.
the Problem with Write IOPS

the "play it again Sam" syndrome
Editor:- Flash SSD "random write IOPS" are now similar to "read IOPS" in many of the fastest SSDs.

So why are they such a poor predictor of application performance?

And why are users still buying RAM SSDs which cost 9x more than SLC? - even when the IOPS specs look similar.
the problem with flash SSD  write IOPS This article tells you why the specs got faster - but the applications didn't. And why competing SSDs with apparently identical benchmark results can perform completely differently. the article
There are many traditional storage subjects like tape, optical, backup software, USB, FireWire etc which have been pushed off our home page in the past year by increased SSD content.

You can still access these directories and articles using the search box above or by going to our alternative (1990s style) very graphical home page below.
click to see traditional storage home page
How many disks does it take to store a disk-full of data?
Sometimes you can learn something useful by asking a silly question which initially seem to have a trivial and obvious answer.
Spellabyte is counting storage drives - click to read the article How many disks does it take to store a disk-full of data? ...And where do the SSDs creep in?

They always seem to sneak into my articles somewhere... You don't need a calculator or spreadsheet for this one. the article
Storage Visions click for more info
Storage Visions

10th anniversary theme...
New Dimensions Drive Digital Storage

Jan 4 - 5, 2011 Riviera Convention Center, Las Vegas, NV
SSD vs HDD failure rates - in retail
storage reliability articles Editor:- December 10, 2010 - failure rates for consumer SSDs and hard drives are compared in new articles linked on the storage reliability page.
Top 20 SSD companies - (quarterly edition)
Editor:- Which companies do you absolutely have to include in your thinking if you've got any new projects involving SSDs?

And which SSD companies are most likely to succeed?

With hundreds of manufacturers already in the SSD market - and hundreds more soon to enter - you have to know where you should prioritize your valuable time and attention.

For more than 3 years has published the quarterly list of the Top 10 SSD companies - which has accurately predicted the ebbs and flows of existing vendors and has been sensitive enough to recognize the industry's new rising stars from the background noise of the SSD bubble's hype.

Unlike editor or analyst pick lists - this is based on the scientific method of tracking and analyzing the search volume of the most important people who will decide the future of the SSD market - the millions of people - who like you have been reading our SSD content.

Each edition of the list includes a list of the top companies and a review an analysis of key SSD market milestones in that quarter. By comparing successive listings you can also see - who is on the way up and who is on the way down.

The listings have been recently expanded to include the top 20 SSD companies.
these are the SSD companies you have to consider on any buyers shortlist - this quarterly series predicts future market winners by tracking search volume of millions of SSD buyers This gives you better visibility of companies are hot on the heels of the leaders in top market segments. the article
Bad block management in flash SSDs
This is an introduction to the thinking behind one of the many vital functions inside a flash SSD controller.

Native media defect quality in new flash memory chips has grown steadily worse in the past 10 years as geometries have shrunk.
click image to read the article - principles of bad block management in flash SSDs This article enumerates the scale of the problem and explains how intrinsically dodgy flash memory is transformed into dependable flash SSDs which you can entrust with your data. the article
Who makes the fastest SSDs?

Speed isn't everything, and it comes at a price.
But if you do need the speediest SSD (chip, card, module or rackmount) then wading through the web sites of hundreds of SSD oems to shortlist products slows you down.

And the SSD search problem will get even worse as we head towards a market with over 1,000 SSD oems.
the fastest SSDs  sorted by interface and form factor - click to read article ... Relax - I've done the research. And this whizzy wish list is updated daily from storage news and direct contacts from oems. the article,
Are MLC SSDs Safe in Enterprise Apps?
This is a follow up article to the popular SSD Myths and Legends which in 2007 demolished the myth that flash memory wear-out (a comfort blanket beloved by many RAM SSD makers at the time) precluded the use of SLC flash in heavy duty datacenters.

Are MLC SSDs Safe? - has also become a classic and very popular article. It looks at the risks posed by MLC Nand Flash SSDs which - having hatched from their breeeding ground as chip modules in cellphones - have morphed and crept into hard disk form factors.

In a notebook (where you aren't exactly aiming for a 99.999% uptime quality data experience) MLC SSDs can be a good thing from the reliability and cost point of view. But in the datacenter?

First published in 2008 this article has been extensively updated in 2010 - to answer common reader questions - and because the risks from newer MLC flash are even greater than they were when the article originally appeared.

It starts down a familiar lane but includes many technology twists. You'll realize that patching the hole in the bottom of the leaking data bucket isn't much good - if the whole bucket can tip over and splash your data beyond ECC limits due to factors which no SSD controller guarantees to protect you from. That's because there's a lot more to MLC data integrity risk than endurance!
are MLC SSDs safe in enterprise apps - recently updated   popular article Knowing what these risks are can help you decide if your enterprise app is inside or outside the vulnerable to data loss zone. the article
SSD Pricing - where does all the money go?
SSDs are among the most expensive computer hardware products you will ever buy and comprehending the factors which determine SSD costs is often a confusing and irritating process...
Clarifying SSD Pricing - where does all the money go? - click to read the article ...which is not made any easier when market prices for apparently identical capacity SSDs can vary more than 100x to 1!

Why is that? the article to find out
SSDs? - the overall market picture
Editor:- was the world's 1st publication to provide continuous editorial coverage and analysis of SSDs (in 1998) and in the years which have followed we've led the market through many interesting and confusing times.
click to read the story about why SSDs are taking up so much time on so many web pages What's the big market picture of the impact of SSDs? - and how big will the SSD market grow in the next several years... This is all you need to know. to read the article