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On his blog post on preparation, Seth Godin mentioned an appropriate Swedish saying:
There is no bad weather, just bad clothing.
Appropriate because it snowed here in Tucson, Arizona on Sunday evening, leaving many of us here figuring out how to drive through the stuff on Monday. In my entire lifetime, I have only witness snow down in the Tucson valley a handful of times. It got me thinking about coats, and the wonderful schemes for coat check rooms, as an analogy for data access. A lot of people ask me to compare and contrast one technology from another, say block-level virtualization from content-addressable storage, and so on, and I always try to find a good analogy to help explain things.
Let's start with the setting. It is snowing outside and people are wearing coats. When they come inside, they check their coats at a coat check room, a large room with rows and rows of racks with hangers. A coat check attendant takes your coat and puts it on a hanger, and gives you a ticket or other identifier that will allow you to retrieve your coat later. The ticket must have sufficient information to retrieve the coat quickly, rather than searching rows and rows of hangers for it.
A problem arises when you generate "hash codes" for storage. It is possible for two different pieces of data to resolve to the same hash code. When an application tries to write a piece of data, and it resolves to a hash code that already exists, that is called a collision. One response is to either compare the incoming data to the data that is already stored, confirm they are identical, but that can be time consuming. The other response is to just assume they are identical, and reject the secondary copy, a process often referred to as "de-duplication".
What's the chance of getting a collision for data that is really different? Let's take for example the famousBirthday paradox. Suppose the coat check room assigned the hanger based on your birthday (month and day). How may coats before you run the risk of having two people turn in coats with the same birthday? After only 23 people, the likelihood is 50%. At 60 people, it goes up to 99%.
For this reason, IBM does not offer content-addressable storage. For non-erasable, non-rewriteable storage, the IBM System Storage DR550 requires the application to give each object a name, and that name is then used to storage the data, eliminating the possibility that data might accidently be thrown away.
It's safer that way.
technorati tags: Seth Godin, Swedish, saying, bad, weather, clothing, snow, Tucson, coat, check, room, IBM, block-based, disk, storage, DR550, N series, NAS, healthcare, life sciences, grid, medical, archive, solution, GMAS, cont
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Continuing my theme on naming conventions, this time I will talk about finding information.
Industry analysts estimate that information workers spend as much as 30 percent of their working day just looking for information they need, as mentioned in an interview withJeff Teper, Microsoft.A second study of middle managers found similar results, and is discussed in Information Architecture andDM Review.
Take for example looking for information on a specific person. If you were searching for"Barack Obama" or "Lulit Shiferaw", then perhaps you will find exactly the person you werelooking for.
On the other hand, some names are more common. I've met my share of people named John Smith, Jennifer Jones,or Mark Johnson. While PEARSON does not even make the top 100 list of family names here in the US, it isstill fairly common.
People looking for me may realize that I am notHead of Australian Economics at ANZ Bank, author of the book "Don't Read This!", winner of the Killam Teaching Prize, or owner offisheries in Essex.While I do work out at the gym on a regular basis, I look nothing like thisfamous body builder. There are several others, but I pickedjust a few to make my point.
At this time, there is only one "Tony Pearson" working at IBM. A while back, there was a second,a woman who spelled her name "Toni" with an "i" at the end. Her job involved deploying storage on AIX platforms,and was similar enough job description to mine that we would get each other's mail, and sometimes not realize it was meant for the other.
Dan Santow of Word Wise talks about the difficulties of proper names withaccent marks.This would make searching worse, but many search tools can handle this, stripping off allaccent marks to make the comparisons.
But what if you wanted to leave those accent marks in, for an exact match?
technorati tags: Jeff Teper, Accenture, search, names, IBM, Barack Obama, Lulit Shiferaw, Dan Santow, Word Wise, productivity, Essex, bodybuilder, author, fish
Stephen Colbert, of The Colbert Report, explains the name changes in recent mergers of the Telecommunications industry. A discussion on "changing names" and how that impacts storage seems like a good way to wrap up the week's theme on naming conventions.
Name changes are sometimes painful, but often times done for a purpose, such as to promote a family. In the US, when a man and woman marries, the woman often changes her family name to match her husband, and the kids all adopt the father's family name. I say "often" because there are times where the woman keeps her name, or adds to it in a hyphenated way. ABC News reported that a Man Fights to Take Wife's Name in Marriage. KipEsquire, a lawyer, writes about it in his blogA stitch in haste.
IT industry changes the names of products that people knew as something else. Other times, they re-use an existing name, when really it is or should be different from the original. Last year, I took on the job of helping transition from our brand "TotalStorage" to the "System Storage" product line under the new "IBM Systems" brand. I help decide what stays the same name or what changes, when it should change, and how to announce that change.
On the disk side, IBM renamed Fibre Array Storage Technology, or FAStT, which was pronounced exactly like "fast", to DS4000 series. This was a big improvement, as people couldn't seem to spell it properly, with variations like "FastT". Nor could people pronounce it properly, saying "fast-tee" instead. The advantage of "DS" is that it is both easy to spell, and easy to pronounce. The DS4000 series continues to be "fast", providing excellent performance for its midrange price category.
IBM's Enterprise Storage Server (ESS) line went from model E10, to F20, to 750 and 800. When IBM came out with its replacement, the IBM TotalStorage DS8000, some people asked why it wasn't named the ESS 900, for example. The DS8000 is quite different internally, new hardware design and implementation, but is highly compatible with the ESS line, and shares much of the same functionality from microcode. Last year, it was replaced by the IBM System Storage DS8000 Turbo. Again, newer hardware, so it was easy to justify the new name change from "TotalStorage" to "System Storage".
Renaming a product risks losing its certifications and awards. For example, IBM spent a lot of time and money getting the OS/390 operating system certified as a "UNIX" platform. When it was renamed to z/OS, IBM had to do it all over again. Learning from this experience, IBM decided not to rename the SAN Volume Controllerto a new designation like "DS5750", as it enjoys the "number one" spot on both the SPC-1 and SPC-2 performance benchmarks, and is recognized as the leader in the disk storage virtualization marketplace. Renaming this product would mean losing that collateral.
IBM's "other disk systems" the N series posed another set of challenges. The current DS line already has entry-level (DS3000), midrange (DS4000) and enterprise-class (DS6000 and DS8000) products. The OEM agreement that IBM has with Network Appliance (NetApp) resulted in a new set of entry-level, midrange, and enterprise-class products. But these didn't fit nicely into the DS3000-to-DS8000 continuum. Instead, IBM decided to go with N series, using N3000 for entry-level, N5000 for midrange, and N7000 for enterprise-class. These are different than the numbers used by NetApp for their comparable, but not identical, offerings.
On the tape side, IBM decided to name the tape drives TS1000 and TS2000 range, tape libraries and automation with a TS3000 range, and tape virtualization to the TS7000 range. A lot of tape products already had 3000 numbering that had to change to fit this new scheme. This is why IBM's popular 3592 tape drive was renamed to the TS1120. The replacement to the 3494 Virtual Tape Server was named TS7700 Virtualization Engine.
Obviously, you can't change the names of products that are currently in the field, but what about existing software with minor updates? IBM decided to leave "TotalStorage Produtivity Center" under the "TotalStorage" brand until it has a significant version upgrade. Many people say "TPC" as a convenient acronym when referring to this product, but TPC is a registered trademark of the Professional Golfers Association (PGA) to refer to its "Tournament Players Club".
How can anyone confuse "managing storage" with "playing golf"? One activity is full of frustration that takes years or decades to master, involving the need to understand a variety of equipment and techniques to use each properly to accomplish your goals; and the other is an enjoyable activity, immediately productive in front of a single pane of glass managing all of your DAS, SAN and NAS storage, from reporting on your files and databases to managing storage networks and tape libraries.
Enjoy the weekend!
technorati tags: Stephen Colbert, Colbert Report, Telecommunications industry, KipEsquire, IBM, FAStT, DS4000, DS3000, DS8000, OS/390, UNIX, z/OS, SAN Volume Controller, N series, TS1120, TS7700, TotalStorage Productivity Center, TPC, PGA, Golf[Read More]
This week I am in Japan, so my week's theme will center around travel, speaking at conferences, and Japan itself. I first travelled to Japan in the late 1980s, to visit a college friend who was working for Ford Motor Company, on assignment in Japan as liasion to Mazda Corp.
Back then, the only Japanese phrase I knew was "Wakarimashta" which means "I know" or "I understand". If you only know one phrase in a foreign language, this possibly could be the worst to know.
My second trip, I was better prepared. I learned three "survival phrases":
sumimasen - "I'm sorry/excuse me"
These are great phrases to know individually, but even more powerful strung all together, to emphasize that you will begin speaking English, but at least with good reason (and perhaps a bit of irony.)
I've been to Japan many times since, and have picked up more of the language. When travelling to Japan, or anywhere for that matter, it is important to "pack light". I'll be gone for two weeks, but all I bring is a laptop bag and one carry-on piece of luggage.
I went on a trip to Prague (Czech Republic) with a female co-worker who brought FOUR pieces of luggage. One was just for shoes. Another piece was just for hair styling gel, make-up, face creams and finger nail polish. Today, the rules are different, and the TSA allows only a single quart-size plastic bag containing little jars of 3 ounces or less of liquids or gels. I didn't have any "quart-size" bags, so I used a smaller sandwich-size bag.
What does all this have to do with storage? I've helped many clients move data centers, and this involves moving their servers, their networks, and their storage. Servers and Networks are easy to move, but storage presents some challenges. In many cases, the entire company is shut down, the storage is moved, and then the company is operational again. Needless to say, it is best to do this over a weekend.
I tell clients to "pack light" and figure out what data they really need in the move. What do you really need to operate your business? Bring just that, the rest can arrive later.
This same concept applies for Business Continuity and Disaster Recovery planning. What do you really need after a disaster occurs? Can you run your business for a few weeks on that data, until the rest of the data is restored? If you can't run your entire business on that data, can you run your most important parts of your business?
If you run a bank, perhaps keeping your ATM cash machines running is more important than making out new loans. In Japan, if a bank has any outages that impact their ATM machines, they put out a full page advertisement in the local papers to apologize for the inconvenience.
Business Continuity is one of the nine "Infrastructure Solutions" that IBM can help clients with. If you are interested in learning more on how IBM can help you with your Business Continuity, click here.
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Continuing my week's theme on travel, conferences, and Japan, I saw two items in the newsthat seem to follow a common theme.
What do these stories have to do with one another, other than both relating to Japan? IBM has beenusing TDMF for years as part of a service offering to move data from one disk system to another.Since Sam Palmiasano took over in 2002, IBM has acquired 51 companies, 31 of them software companies.Often, these have been "successful" turning quickly profitable because IBM was already well familiar with the companies they acquire, in much the same way that husbandsare well familiar with their brides-to-be at a "double happy wedding".
So, welcome Softek! It looks like its time to celebrate again!
Well, I have left Japan, and while everyone else is enjoying the Super Bowl, I am now in Australia, at another conference.Today I had the pleasure to hear filmmakers talk about their successes, and how IBM helps the movie industry.
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In Storage Technology News, Marc Staimer makes hisSeven network storage predictions for 2007. Let's take a closer look at each one.
technorati tags: IBM, FRCP, SOX, TotalStorage, Productivity Center, Microsoft, Exchange, Lotus, Domino, DR550, SnapLock, unified storage, NAS, iSCSI, FCP, ROBO, Tivoli, Storage Manager, TSM, Ethernet, AoE, CDP, DB2, Oracle, SAP, VTL, TS7700, TS7510, GPFS, DFSMS, Optical, 3995, 3996, Blue-Ray, D2D2T,DVD[Read More]
I am back from China, and now glad to be back in the old USA. Last week, someone asked me what would it take to add a specific feature to the IBM System Storage DS8300. The what-would-it-take question is well-known among development circles informally as a "sizing" effort, or more formally as "Development Expense" estimate.
For software engineering projects, the process was simply that an architect would estimate the number of "Lines of Code" (LOC) typically represented in thousands of lines of code (KLOC). This single number would convert to another single number, "person-months", which would then translate to another single number "dollars". Once you had KLOC, the rest followed directly from a formula, average or rule-of-thumb.
More amazing is that this single number could then determine a variety of other numbers, the number of total months for the schedule, the number of developers, testers, publication writers and quality assurance team members needed, and so on. Again, these were developed using a formula, developed and based on past experience of similar projects.
Earlier in my career, I was the lead architect for DFSMS for the z/OS operating system, and later for IBM TotalStorage Productivity Center, performing these sizing efforts. A famous IBM architect, Frederick P. Brooks, wrote a now-classic book that was requiredreading when I started at IBM, which just was re-released as Mythical Man-Month: Essays in Software Engineering, 20th Anniversary Edition. In addition to sound advice, he alsooffered a formula or two that helps with these estimating tasks.
Hardware design introduces a different set of challenges. When I was getting my Masters Degree in Electrical Engineering, it took myself and four other grad students a full semester just to design a six-layer, 900 transistor silicon chip, which could only perform a single function, multiply two numbers together.At IBM, another book that I was given to read was Soul of a New Machine, documenting six hardware engineers, and six software engineers, working long hours on a tight schedule to produce a new computer for Data General.
So why do I bring this up now? IBM architects William Goddard and John Lynott are being inducted posthumously this year into the prestigious National Inventors Hall of Fame for their disk system innovation.
Under the leadership of Reynold Johnson, the team developed an air-bearing head to “float” above the disk without crashing into the disk. Imagine a fighter airplane flying full speed across the country-side at 50 feet off the ground. If you every heard the term "my disk crashed", it was originally referring to the read/write head touching the disk surface, causing terrible damage.
A uniformly flat disk surface was created by spinning the coating onto the rapidly rotating disk, leaving many wearing lab coats covered with disk liquid at waist level. Developing disk-to-disk and track-to-track access mechanisms proved more challenging, and nearly halted the project. The team, however, was adamant that this problem could be solved, and customers were increasingly asking for random access technology. The result was the "350 Disk Storage Unit" designed for the "305 RAMAC computer", which I have talked about a lot last year as part of our "50 years of disk systems innovation" celebration.
Neither Goddard nor Lynott had computing experience prior to joining IBM. Goddard was a former science teacher who briefly worked in aerospace. Lynott had been a mechanic in the Navy and later a mechanical engineer. They didn't have a nice formula based on past experience, they didn't have the benefit of Fred Brooks' advice, or the rules-of-thumb or averages now used to estimate the size of projects. They had to break new ground.
Now that's innovation!
technorati tags: IBM, DS8300, disk, KLOC, sizing, estimate, DFSMS, z/OS, TotalStorage Productivity Center, Frederick Brooks, William Goddard, John Lynott, Mythical Man-Month, Reynold Johnson, RAMAC, 305, 350,[Read More]
In case you haven't noticed, IBM System Storage makes most of their announcements on Tuesdays. IBM announced a lot today, so here is a quick run-down.
IBM continues its market leadership with these new set of features and offerings!
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I am still wiping the coffee off my computer screen, inadvertently sprayed when I took a sip while reading HDS' uber-blogger Hu Yoshida's post on storage virtualization andvendor lock-in. This blog appears to be the text version of theirfunny video.
While most of the post is accurate and well-stated, two opinions particular caught my eye. I'll be nice and call them opinions, since these are blogs, and always subject to interpretation. I'll put quotes around them so that people will correctly relate these to Hu, and not me.
"Storage virtualization can only be done in a storage controller. Currently Hitachi is the only vendor to provide this."
Hu, I enjoy all of your blog entries, but you should know better. HDS is fairly new-comer to the storage virtualization arena, so since IBM has been doing this for decades, I will bring you and the rest of the readers up to speed. I am not starting a blog-fight, just want to provide some additional information for clients to consider when making choices in the marketplace.
First, let's clarify the terminology. I will use 'storage' in the broad sense, including anything that can hold 1's and 0's, including memory, spinning disk media, and plastic tape media. These all have different mechanisms and access methods, based on their physical geometry and characteristics. The concept of 'virtualization' is any technology that makes one set of resources look like another set of resources with more preferable characteristics, and this applies to storage as well as servers and networks. Finally, 'storage controller' is any device with the intelligence to talk to a server and handle its read and write requests.
Second, let's take a look at all the different flavors of storage virtualization that IBM has developed over the past 30 years.
So, bottom line, storage virtualization can, and has, been delivered in the operating system software, in the server's host bus adapter, inside SAN switches, and in storage controllers. It can be delivered anywhere in the path between application and physical media. Today, the two major vendors that provide disk virtualization "in the storage controller" are IBM and HDS, and the three major vendors that provide tape virtualization "in the storage controller" are IBM, Sun/STK, and EMC. All of these involve a mapping of logical to physical resources. Hitachi uses a one-for-one mapping, whereas IBM additionally offers more sophisticated mappings as well.
Today, I went looking for reading-glasses. Unfamiliar with my surroundings, I asked several people where I might be able to find and purchase these, and was sent in various directions. My first stop was a bookstore. It would make sense that since many people need reading glasses to read the books, that they would sell them there, but no. The staff didn't know where I could go, but pointed me in the direction of a mall. At the mall, I found a pharmacy. Many pharmacies sell reading glasses, so I stopped in, but no, not this one. The pharmacists suggested the super-store nearby. I walked in to the super-store, and asked the first employee where they keep their reading glasses, and they said the other corner. The other corner was the electronics department. It made sense that they sold CDs and DVDs in the same section as the equipment that plays them, but reading glasses? Skeptical, I went to the pharmacy department, and the young and beautiful lady (everyone is young, thin and beautiful here) had me follow her, and she led me back to the electronics department, whereupon she pointed to a rack of sunglasses. I indicated that I need reading glasses, not sunglasses. She pulled one out, and it was indeed reading glasses, 1.25, just what I was looking for. Others were tinted, so you can read the newspaper out in the sunlight. The pair I chose cost only $97 in the local currency.
After reading the last sentence, you might be thinking I am describing my "avatar" in Second Life, but no, I am talking about my search for reading glasses on the streets of Mexico. I am here this week in meetings with IBM Business Partners and sales reps to discuss IBM's latest System Storage products and offerings.
We used to tell people they should "clothe" servers with storage. IBM offers both, so yes it makes sense to offer both as part of a complete solution. However, when you look through a dictionary definition "to clothe" you learn it is to dress, wrap or cover with clothing, an implication that it is external, and perhaps temporary, easily changed, like switching from sunglasses to reading glasses. In Second Life, objects can be "worn", simply by attaching or detaching them to your "avatar". Sometimes clothing serves a purpose, like reading glasses, provides protection, like raincoats, and other times, more decorative, like"icing on the cake" or "gold plating".
This concept was fine 50 years ago, when we were in a server-centric world, and dumb storage devices were attached to very intelligent servers. Back then, we used the derogatory term "subsystems" to emphasize that storage was just part of the server, not a system of its own.
Today, we live in an information-centric world. The information outlives the media, and the media outlives the servers that access it. It is not unreasonable to attach dozens or hundreds of servers to a single storage system, or collection of storage systems. Over 20 percent of IBM System Storage DS8000 series, for example, are attached to Windows rack-optimized or blade servers. Imagine a refrigerator surrounded by dozens or hundreds of pizza boxes. Storage is no longer a subsystem, but a system on its own right, dressed, wrapped or covered by servers that deliver the right information, to the right people, at the right time.
So perhaps we should reverse it, telling people they should "clothe" their storage with servers!
Well, I'm back from Mexico.
The flight back was uneventful, except for the leg from Houston to Tucson. The lady in the window seat had "overallocated storage" and required a "distance extension" on her safety belt. To accomodate her, her husband and I flipped up the "logical partitions" between the seats, and "compressed" to take up less space to accomodate. Luckily, it was only for two hours.
On the flight to Houston, I was asked what kind of drink I wanted, in Spanish, as the crew were all from Mexico. Here's a quick Spanish lesson:
Before IBM got into an OEM agreement with Network Appliance, I used to indicate that EMC and NetApp were the "Coke and Pepsi" of the NAS marketplace. IBM had a presence, but it was in the single digits, whereas these two major players had roughly equal marketshare, just as Coke and Pepsi dominate equally the US marketplace. That analogy doesn't work in other countries, as in some cases the country might be more heavily in favor of one or the other.
On my flight over from Houston to Tucson, however, I was asked what kind of "pop" I wanted. I always say "soda" to refer generically to soft drinks, but realize that others say "pop" instead. Not only can Americans be able to detect what part of the country people are from by accent, but also by the words they use.
Now I see a blog that explores in great detail the issue of Pop vs Soda vs Coke.
So, it looks like I'll need to "retire" my Coke vs. Pepsi analogy, not because their marketshare has changed, but because IBM's parntering with NetApp greatly skews the advantage over EMC.
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Tonight I had dinner with Henry Daboub (an SVC expert from Houston, TX) and some clients, who asked what I would blog about tonight, and I figured it made sense to blog about the SVC.
Hu Yoshida clarifies his position about storage virtualization, including the statement: "As a result they can not provide the availability, scalability, and performance of a DS8300. If they could, there would be no need for a DS8300."
Of course, if humans descended from apes, why are there still apes? Now that we have cars, why are there still trains? But perhaps a better question is: now that there are supercomputers, why are there still mainframe servers?
The issue is the difference between scale-up versus scale-out. Scale-up is making a single box as big and beefy as possible. When the SVC was introduced, the major vendors all had scale-up designs: IBM ESS 800, HDS Lightning, EMC Symmetrix. Like the mainframe, they were for customers that wanted everything in a single monolithic container.
SAN Volume Controller was the result of IBM Research asking the question, if you could put anyone's software (feature and functionality) on anyone's hardware (monolithic scale-up design), what combination would you choose? What if the brains inside today's monolithic systems could be snapped into the another vendor's frame? What if you could run SRDF on an HDS box, or ShadowImage on an IBM box? The surprising response was that most customers would want a single software for consistency, but wanted the option to choose from different vendors hardware, to negotiate the best price of the commodity iron. Based on this feedback, the SVC was born.
The idea was simple, put all the brains in a separate appliance. The appliance would do the non-disruptive migrations, the caching, the striping, and all the copy services. This lets the customer chose then the hardware they want, any mix of FC and ATA disk, from any vendor.
The SVC design was based on IBM's long history in supercomputers. Using the same "scale-out" technology, the power comes not from having it all in one monolithic box, but rather in a design that combines small nodes together. While the cache is not globally shared, the data is shared between node-pairs, and the logical-to-physical mapping is routed around to all nodes in a cluster. Each SVC node talks to each other SVC node through the FCP ports, eliminating the need for additional wiring. For the most part, each node does its own separate work, but when it needs to, they can communicate across, just like nodes in a supe Both the SVC and the DS8300 Turbo have better than 99.999 percent availability, based on redundant components designed for no single point of failure (SPOF). IBM has sold thousands of each, and they have been in the field enough time that we can make that claim. There is nothing between scale-up versus scale-out that makes on inherently more available than the other. Both the SVC and the DS8300 Turbo can scale from as little as a few TB of disk, to hundreds of TB of disk. We have yet to meet a customer that is too big for the SVC. The DS8300 Turbo is able to scale by adding up to four extension frames, but is still considered a single box from a scale-up perspective. From a processor perspective, an 8-node SVC cluster has 16 Intel Xeon processors, and the DS8300 has 8 POWER5+ processors (dual 4-way). The key advantage of scale-out is that you can add capacity to the SVC in smaller increments. Jumping from a DS8100 (dual 2-way) to a DS8300 (dual 4-way) is a big jump. SVC remains the fastest disk system in the industry, based on both the SPC-1 and SPC-2 benchmarks. The latest model now supports 8GB per node, for a total of 64GB for an 8-node cluster. This can be used for both read and write non-volatile storage. By comparison, DS8300 Turbo has 32GB write non-volatile storage, and up to 256 GB of read-only cache. The SVC is able to do 155,519 IOPS, faster than the 123,030 IOPS for the DS8300, and of course faster than anything from EMC, HDS, HP or Texas Memory Systems. Of course, workloads vary, and there might be some workloads where the 256GB of read-only cache of the monolithic DS8300 is the better choice. Both SVC and DS8300 Turbo offer FlashCopy (point-in-time copy), Metro Mirror (synchronous) and Global Mirror (asynchronous). SVC provides the additional benefit that it can perform a FlashCopy from one frame to another, and the ability to migrate data seemlessly from one box to anot
Both the SVC and the DS8300 Turbo have better than 99.999 percent availability, based on redundant components designed for no single point of failure (SPOF). IBM has sold thousands of each, and they have been in the field enough time that we can make that claim. There is nothing between scale-up versus scale-out that makes on inherently more available than the other.
Both the SVC and the DS8300 Turbo can scale from as little as a few TB of disk, to hundreds of TB of disk. We have yet to meet a customer that is too big for the SVC. The DS8300 Turbo is able to scale by adding up to four extension frames, but is still considered a single box from a scale-up perspective. From a processor perspective, an 8-node SVC cluster has 16 Intel Xeon processors, and the DS8300 has 8 POWER5+ processors (dual 4-way). The key advantage of scale-out is that you can add capacity to the SVC in smaller increments. Jumping from a DS8100 (dual 2-way) to a DS8300 (dual 4-way) is a big jump.
SVC remains the fastest disk system in the industry, based on both the SPC-1 and SPC-2 benchmarks. The latest model now supports 8GB per node, for a total of 64GB for an 8-node cluster. This can be used for both read and write non-volatile storage. By comparison, DS8300 Turbo has 32GB write non-volatile storage, and up to 256 GB of read-only cache. The SVC is able to do 155,519 IOPS, faster than the 123,030 IOPS for the DS8300, and of course faster than anything from EMC, HDS, HP or Texas Memory Systems. Of course, workloads vary, and there might be some workloads where the 256GB of read-only cache of the monolithic DS8300 is the better choice.
Both SVC and DS8300 Turbo offer FlashCopy (point-in-time copy), Metro Mirror (synchronous) and Global Mirror (asynchronous). SVC provides the additional benefit that it can perform a FlashCopy from one frame to another, and the ability to migrate data seemlessly from one box to anot
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Well, this week I am in Maryland, just outside of Washington DC. It's a bit cold here.
Robin Harris over at StorageMojo put out this Open Letter to Seagate, Hitachi GST, EMC, HP, NetApp, IBM and Sun about the results of two academic papers, one from Google, and another from Carnegie Mellon University (CMU). The papers imply that the disk drive module (DDM) manufacturers have perhaps misrepresented their reliability estimates, and asks major vendors to respond. So far, NetAppand EMC have responded.
I will not bother to re-iterate or repeat what others have said already, but make just a few points. Robin, you are free to consider this "my" official response if you like to post it on your blog, or point to mine, whatever is easier for you. Given that IBM no longer manufacturers the DDMs we use inside our disk systems, there may not be any reason for a more formal response.
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Tuesday is always good for announcements. Today, Gartner, Inc. announced that IBM has taken over HP in its climb to the top. I'll quote directly from today's press release:
STAMFORD, Conn., March 6, 2007 — Worldwide external controller-based (ECB) disk storage revenue totaled $15.2 billion in 2006, a 4.1 percent increase over 2005 revenue of $14.6 billion, according to Gartner, Inc.IBM overtook Hewlett-Packard for the No. 2 position in 2006 (see Table 1). IBM’s worldwide ECB market share increased to 15.8 percent, while HP’s market share dropped to 13.1 percent.
IBM beat HP both in 4Q06, as well as 2006 full year.You can read more about it from Gartner Dataquest report “Market Share: Disk Array Storage, All Regions, All Countries, 1Q05-4Q06" on their website. (Note: non-IBMers might need an account with Gartner to access this, not sure)
The focus was on external controller-based disk, not external controller-less SCSI/SAS disk, not disk arrays posing as virtual tape libraries, nor any disk sold inside HP, Sun, IBM or Dell servers. This is to compare with disk-only vendors such as EMC and HDS. The revenues reflect hardware only, including hardware-related parts of financial leases and managed services. Revenues from optional priced software features such as multi-pathing drivers, management software, or advanced copy services were excluded.I discussed these types of analyst reports back in blog post last September: Space Race Heats Up.
These marketshare numbers are based on revenues, not units or terabytes. When a box gets sold, the revenue was counted toward the vendor that sold it, not the manufacturer that built it. In this last report: