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Tony Pearson is a Master Inventor, Senior IT Architect and Event Content Manager for [IBM Systems for IBM Systems Technical University] events. With over 30 years with IBM Systems, Tony is frequent traveler, speaking to clients at events throughout the world.
Lloyd Dean is an IBM Senior Certified Executive IT Architect in Infrastructure Architecture. Lloyd has held numerous senior technical roles at IBM during his 19 plus years at IBM. Lloyd most recently has been leading efforts across the Communication/CSI Market as a senior Storage Solution Architect/CTS covering the Kansas City territory. In prior years Lloyd supported the industry accounts as a Storage Solution architect and prior to that as a Storage Software Solutions specialist during his time in the ATS organization.
Lloyd currently supports North America storage sales teams in his Storage Software Solution Architecture SME role in the Washington Systems Center team. His current focus is with IBM Cloud Private and he will be delivering and supporting sessions at Think2019, and Storage Technical University on the Value of IBM storage in this high value IBM solution a part of the IBM Cloud strategy. Lloyd maintains a Subject Matter Expert status across the IBM Spectrum Storage Software solutions. You can follow Lloyd on Twitter @ldean0558 and LinkedIn Lloyd Dean.
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Continuing this week's theme of New Year's Resolutions for the data center, today we'll talk about one that many people make for their own personal lives: staying on a budget.
Often, when faced with a tightening budgets, we try to make more use of what we already have. Tell someone they are only using 10 percent of their brain, and they immediatelybelieve you; but tell them they are only using 30 percent of their storage, and they ask for a whitepaper,magazine article, or clarification on how that percentage is calculated. I actually visiteda customer that was only using6 percent of the storage attached to their Windows servers!
So, to help those of you making data center resolutions to stay on budget, the terms to remember are "Reduce", "Reuse" and "Recycle".
When people come to request storage, are they being reasonable about what they need today, or are they asking for what they might need over the next three years? They might need 50GB, but they ask for 100GB, in case they grow, and a year later, you find they have only 15GB of data on it. On the flipside, the person asks for what they need but some storage admins give out more, just so they don't have to be bothered so often when growth happens. Finally, I have seen this formalized into fixed size LUNs, all the disk is carved into big huge 100GB pieces, so if you need 20GB, here's one big enough with plenty of room to grow.
If you are going to keep on a budget, remember that storage today is 30% more expensive than storage next year. That is the average drop in both disk and tape on a dollar-per-MB basis. If there is any way to postpone giving out storage until it is actually needed, you can save a bundle of money. Timing is everything! In the event of a disaster, getting immediate replacement for disk can be very expensive, but if you can wait just two weeks, you can negotiate a better deal. I thought of this while going to the movie theatre yesterday. A "hot dog" and a bottle of water was $8.00, but if you are able to wait two hours and eat after the movie, you can get a much better meal for less.
A lot of companies buy new storage because their existing storage isn't fast enough, or doesn't have the latest copy services. This can easily be solved with an IBM SAN Volume Controller (SVC). The SVC can virtualize slower, functionless storage, and present to your application hosts virtual disks that are faster, and with all the latest disk-to-disk copy services like FlashCopy, Metro Mirror, and Global Mirror.
Chances are, you have unused disk capacity spread across all your storage today, but perhaps they are formatted into small LUNs. The SVC can combine the capacity, and let you carve up big LUNs at the sizes you need.This is like taking all those tiny pieces of soap in your shower and forming a new bar of soap, or taking all the crumbs at the bottom of your bread box, and making a new slice of bread. And, the virtual LUNs are dynamically expandable,so give out only the amount they need today, as it is simple to expand them to larger sizes later.
Of my 13 patents, the first will always be my favorite, on a function called "RECYCLE" for the Data Facility Storage Management Subsystem Hierarchical Storage Manager (DFSMShsm) product, which is now a component of the IBM z/OS operating system. Basically, tapes could contain hundreds or thousands of files, such as backup versions or archive copies, and these expired on different dates. As a result, a tape would be written100 percent full, and then over time, decrease in valid data to 80, 60, 40, 20 until it hit 0 percent. In some cases, a single filecould hold an entire tape hostage. RECYCLE was able to read the valid data off tapes that were perhaps less than 20 percent full, and consolidate them onto fewer tapes. As a result, a whole bunch of tapes could be returned to the scratch pool, and reused immediately for other workloads. This also helps in moving to newer, higher capacity cartridges, such as the new 700GB cartridge that IBM co-developed with FujiFilm.(This RECYCLE function exists in our IBM Tivoli Storage Manager software, as well as our Virtual Tape Server, but is called "reclamation" instead, to avoid confusion on searches.)
When evaluating your use of tape, determine if you are making best use of the tapes you have now, and perhaps a RECYCLE (or reclamation) scheme may be in order. Fewer tapes can save money in many ways, such as reduced storage costs, and reduced courier costs to send the tapes offsite. Tape media can still be 10-20 times less expensive than disk, based on full capacity.
This year I resolve to be more consistent in my blogging, and my goal is to give you one to five entries per week, every week, based on the advice from Glenn Wolsey, Jennette Banks, and others.On some weeks, I will have a running theme, so rather than super-long entries to cover everything I can think of on a topic, make the entries short and readable. This week is a good time to review last year's "New Year's Resolutions" and to make new ones for 2007. I will discuss actions that companies can adopt for their data centers.
A common resolution is to lose weight, as in this Dilbert comic. Last year, I resolved to lose weight in 2006, and am delighted with myself that I lost eight pounds. When people ask for the secret of my success, I whisper in their ear "Eat less, exercise more." In general, people (and companies) know what to do, but just don't do it, which Pfeffer and Sutton document in their book The Knowing-Doing Gap. In my case, it involved lifestyle change: I exercised at a gym three times per week in Tucson, with a personal trainer, and revamped my diet.
Not everyone subscribes to the "eat less exercise more" philosophy. For example, Ric Watson argues in his blog that you can eat fewer calories, but eat more in actual volume, by choosing the right foods. This brings up the issues of "metrics" that most data centers are familiar with. Last year, I read the book "You: On a Diet" which explains that it is better to focus on "waist reduction" as measured in inches around your mid-section at the belly button, than "weight reduction" as measured in pounds. This year, I resolve to get down to 35 inches by the end of 2007.
The problem with measuring "weight" is that you are weighing bones, muscle and fat. A person can gain ten pounds of muscle, lose ten pounds of fat, and the scale would indicate no progress. The same problem occurs in data centers. How many TB of data do you have? Storage admins can easily tell you, but can they tell how much of this is bone (data needed for operating infrastructure), muscle (data used in daily operations that generates revenue) or fat (obsolete or orphaned data)?
We at IBM often state that "Information Lifecycle Management (ILM)" is more lifestyle change than a "fad diet". Figuring out what data you should capture in the first place, where to place it, when to move it, and when to get rid of it, is more important that just buying different tiers of storage hardware. So, for those looking to make new data center resolutions, I suggest the following actions:
Re-evaluate the metrics you now use, and determine if they are helpful in making decisions and taking action.
Come up with new ones that are more focused to solve the issues you face.
Consider storage infrastructure software, such as IBM TotalStorage Productivity Center, to help you gather the information about your SAN, disk and tape systems, calculate the metrics, and automate the appropriate actions.
For those of us in the northern hemisphere, yesterday was this year's Winter Solstice, representingthe shortest amount of daylight between sunrise and sunset. So today, I thought I would blog on my thoughtsof managing scarcity.
Earlier in my career, I had the pleasure to serve as "administrative assistant" to Nora Denzel for the week at a storage conference. My job was to make her look good at the conference, which if you know Nora, doesn't take much. Later, she left IBM to work at HP, and I gotto hear her speak at a conference, and the one thing that I remember most was her statement that thewhole point of "management" was to manage scarcity, as in not enough money in the budget,not enough people to implement change, or not enough resources to accomplish a task.(Nora, I have no idea where you are today, so if you are reading this, send me a note).
Of course, the flip-side to this is that resources that are in abundance are generallytaken for granted. Priorities are focused on what is most scarce. Let's examine some of theresources involved in an IT storage environment:
Capacity - while everyone complains that they are "running out of space", the truth is that most external disk attached to Linux, UNIX, or Windows systems contain only 20-40% data. Many years ago, I visitedan insurance company to talk about a new product called IBM Tivoli Storage Manager. This company had 7TB of disk on their mainframe,and another 7TB of disk scattered on various UNIX and Windows machines. In the room were TWO storage admins for
the mainframe, and 45 storage admins for the distributed systems. My first question was "why so many people forthe mainframe, certainly one of you could manage all of it yourself, perhaps on Wednesday afternoons?" Their response was that they acted as eachother's backup, in case one goes on vacation for two weeks. My follow-up question to the rest of the audience was:"When was the last time you took two weeks vacation?" Mainframes fill their disk and tape storage comfortablyat over 80-90% full of data, primarily because they have a more mature, robust set of management software, likeDFSMS.
Labor - by this I mean skilled labor able to manage storage for a corporation. Some companies I have visitedkeep their new-hires off production systems for the first two years, working only on test or development systemsonly until then. Of course, labor is more expensive in some countries than others. Last year, I was doing a whiteboard session on-site for a client in China, and the last dry-erase pen ran out of ink. I asked for another pen, and they instead sent someone to go re-fill it. I asked wouldn't it be cheaper just to buy another pen, and they said "No, labor is cheap, but ink is expensive." Despite this, China does complain that there is a shortage of askilled IT labor force, so if you are looking for a job, start learning Mandarin.
Power and Cooling - Most data centers are located on raised floors, with large trunks of electrical power and hugeair conditioning systems to deal with all the heat generated from each machine. I have visited the data centers ofclients that are forced now to make decisions on storage based on power and cooling consumption, because the coststo upgrade their aging buildings are too high. Leading the charge is IBM, with technology advancements in chips, cards, and complete systems that use less power, and generate less heat. While energy is still fairly cheap in the grand scheme of things, fears ofGlobal Warmingand declining oil supplies, the costs ofpower and cooling have gotten some news lately. In 1956, Hubbert predicted US would reach peak oil supplies by1965-1970 (it happened in 1971), and this year Simmonsestimated that world-wide oil production began its decline already in 2005. Smart companies like Google have movedtheir server farms to places like Oregon in the Pacific Northwest for cheaper hydroelectric power.
Bandwidth - Last year IBM introduced 4Gbps Fibre Channel and FICON SAN networking gear, along with the servers and storage needed to complete the solution. 4Gbps equates to about 400 MB/sec in data throughput. By comparison, iSCSI is typically run on 1Gbps Ethernet, but has so much overheads that you only get abour 80 MB/sec. Next year, we may see both 8 Gbps SAN, and 10 GbE iSCSI, to provide 800 MB/sec throughputs. My experience is that the SAN is not the bottleneck, instead people run out of bandwidth at the server or storage end first. They may not have a million dollars to buy the fastest IBM System p5 servers, or may not have enough host adapters at the storage system end.
Floorspace - I end with floorspace because it reminds me that many "shortages" are temporary or artificially created. Floorspace is only in short supply because you don't want to knock down a wall, or build a new building, to handle your additional storage requirements.In 1997, Tihamer Toth-Fejel wrote an article for the National Space Society newsletter that estimated that ...Everybody on Earth could live comfortably in the USA on only 15% of our land area, with a population density between that of Chicago and San Francisco. Using agricultural yields attained widely now, the rest of the U.S. would be sufficient to grow enough food for everyone. The rest of the planet, 93.7% of it, would be completely empty.Of course, back in 1997 the world population was only 5.9 billion, and this year it is over 6.5 billion.
This last point brings me back to the concept of food, and I am not talking about doughnuts in the conference room, or pizza while making year-end storage upgrades. I'm talking aboutthe food you work so hard to provide for yourself and your family. The folks at Oxfam came up with a simpleanalogy. If 20 people sit down at your table, representing the world’s population:
3 would be served a gourmet, multi-course meal, while sitting at decorated table and a cushioned chair.
5 would eat rice and beans with a fork and sit on a simple cushion
12 would wait in line to receive a small portion of rice that they would eat with their hands while sitting on the floor.
So for those of you planning a special meal next Monday, be thankful you are one of the lucky three, and hopefulthat IBM will continue to lead the IT industry to help out the other seventeen.
You may not be the right person to ask but I am asking everyone so "How do you see hybrid disk drives?"
(For the record, I am not immediately related to Robert. At onepoint, "Pearson" was the 12th most common surname in the USA, but now doesn't even make the Top 100.)
Robert, I would like to encourage you and everyone else to ask questions, don't worry if I am the wrong person to ask, asprobably I know the right person within IBM. Some people have called me the "Kevin Bacon" of Storage,as I am often less than six degrees away from the right person, having worked in IBM Storage for over 20 years.
For those not familiar with hybrid drives, there is a good write-up in Wikipedia.
Unfortunately, most of the people I would consult on this question, such as those from Market Intelligence or Research, are on vacation for the holidays, so, Robert, I will have to rely on my trusted 78-card Tarot deck and answer you with a five-card throw.
Your first card, Robert, is the Hermit. This card represents "introspection". The best I/O is no I/O, which means that if applications can keep the information they need inside server memory, you can avoid the bus bandwidth limitations to going to external storage devices. Where external storage makes sense is when data is shared between servers, or when the single server is limited to a set amount of internal memory. So, consider maxing out the memory in your server first (IBM would be glad to sell you more internal memory!!!), then consider outside solid-state or hybrid devices. Windows for example has an architectural limit of 4GB.
Your second card, Robert, is the Four of Cups, representing "apathy".On the card, you see three cups together, with the fourth cup being delivered from a cloud. This reminds me thatwe have three storage tiers already (memory,disk,tape), and introducing a fourth tier into the mix may not garnermuch excitement. For the mainframe, IBM introduced a Solid-State Device, call the Coupling Facility, which can be accessed from multipleSystem z servers. It is used heavily by DFSMS and DB2 to hold shared information. However, given some customer's apathytowards Information Lifecycle Management which includes "tiered storage", introducing yet another tier that forcespeople to decide what data goes where may be another challenge.
Your third card, Robert, is the Chariot, which represents "Speed, Determination,and Will". In some cases, solid state disk are faster for reading, but can be slower for writing. In the case of ahybrid drive, where the memory acts as a front-end cache, read-hits would be faster, but read-misses might be slower.While the idea of stopping the drives during inactivity will reduce power consumption, spinning up and slowing downthe disk may incur additional performance penalties. At the time of this post, the fastest disk system remains the IBM SAN Volume Controller, based on SPC-1 and SPC-2 benchmarks in excess of those published for other devices.
Your fourth card, Robert, is the Eight of Pentacles, which represents"Diligence, Hard work". The pentacles are coins with five-sided stars on them, and this often represents money.Our research team has projected that spinning disk will continue to be a viable and profitable storage media for at least anothereight years.
Your fifth and last card, Robert, is the World, which normallyrepresents "Accomplishment", but since it is turned upside down, the meaning is reversed to "Limitation". Some Hybriddisks, and some types of solid state memory in general, do have limitations in the number of write cycles they can handle. For thoseunhappy with the frequency and slowness for rebuilds on SATA disk may find similar problems with hybrid drives.For that reason, businesses may not trust using hybrid drives for their busiest, mission-critical applications, but certainlymight use it for archive data with lower write-cycle requirements.
The tarot cards are never wrong, but certainly interpretations of the cards can be.