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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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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.
Continuing our exploration this week into the performance of disk systems, today I will cover the metrics to measure performance. Why do people have metrics?
Help provide guidance in decision making prior to purchase
Help manage your current environment
Help drive changes
Several bloggers suggested that perhaps an analogy to vehicles would be reasonable, given that cars and trucks are expensive pieces of engineering equipment, and people make purchase decisions between different makes and models.
In the United States, the Environmental Protection Agency (EPA) government entity is responsible for measuringfuel economy of vehicles using the metric Miles Per Gallon (mpg).Specifically, these are U.S. miles (not nautical miles) and U.S. gallons, not imperial gallons. It is importantwhen defining metrics that you are precise on the units involved.
Since nearly all vehicles are driven by gallons of gasoline, and travel miles of distance, this is a great metric to use for comparing all kinds of vehicles, including motorcycles, cars, trucks and airplanes. The EPA has a fuel economy website to help people make these comparisons.Manufacturers are required by law to post their vehicles' fuel-economy ratings, as certified by the federal Environmental Protection Agency (EPA), on the window stickers of most every new vehicle sold in the U.S. -- vehicles that have gross-vehicle-weight ratings over 8,500 pounds are the exception.
What about storage performance? What could we use as the "MPG"-like metric that would allow you to compare different makes and models of storage?
The two most commonly used are I/O requests per second (IOPS) and Megabytes transferred per second (MB/s). To understand the difference in each one, let's go back to our analogy from yesterday's post.
(A woman calls the local public library. She picks up the phone, and dials the phone number of the one down the street. A man working at the library hears the phone ring, answers it with "Welcome to the Public Library! How can I help you?" She asks "What is the capital city of Ethiopia?" He replies "Addis Ababa" and hangs up. Satisfied with this response, she hangs up. In this example, the query for information was the I/O request, initiated by the lady, to the public library target)
In this example, it might have only taken 1 second to actually provide the answer, but it might have taken 10-30 seconds to pick up the phone, hear the request, respond, and then hang up the phone. If one person is able to do this in 10 seconds, on average, then he can handle 360 questions per hour. If another person takes 30 seconds, then only 120 questions per hour. Many business applications read or write less than 4KB of information per I/O request, and as such the dominant factor is not the amount of time to transfer the data, but how quickly the disk system can respond to each request. IOPS is very much like counting "Questions handled per hour" at the public library. To be more specific on units, we may specify the specific block size of the request, say 512 bytes or 4096 bytes, to make comparisons consistent.
Now suppose that instead of asking for something with a short answer, you ask the public library to read you the article from a magazine, identify all the movies and show times of a local theatre, or recite a work from Shakespeare. In this case, the time it took to pick up the phone and respond is very small compared to the time it takes to deliverthe information, and could be measured instead in words per minute. Some employees of the library may be faster talkers, having perhaps worked in auction houses in a prior job, and can deliver more words per minute than other employees. MB/s is very much like counting "Spoken words per minute" at the public library. To be more specific on units, we may request a specific amount of information, say the words contained in "Romeo and Juliet", to make comparisons consistent.
Now that we understand the metrics involved, tomorrow we can discuss how to use these in the measurement process.
HealthAlliance Hospital has implemented an IBM System Storage Grid Medical Archive Solution (GMAS) to make patient records available to clinicians anytime, anywhere. IBM has a [Case Study] on this implementation.Here is an excerpt from the IBM [Press Release]:
HealthAlliance Hospital, a member of UMass Memorial Health Care, serves the communities of north-central Massachusetts and southern New Hampshire with acute care facilities, a cancer center, outpatient physical therapy facilities and a remote home health agency. As an investment in continued high-quality patient care, the hospital has implemented a picture archiving and communication system (PACS) from Siemens Medical Solutions so that it can move toward digital health records while eliminating traditional paper and film.
HealthAlliance is now able to make all of their data, including PACS images, available instantly, using the IBM GMAS, a cross-IBM offering comprised of storage, software, servers and services. The GMAS solution provides hospitals, clinics, research institutions and pharmaceutical companies with an automated and resilient enterprise storage archive for delivering medical images, patient records and other critical healthcare reference information on demand.
"Fast, easy access to diagnostic images is a priority," said Rick Mohnk, Vice President and Chief Information Officer of HealthAlliance. "Being paperless not only helps our staff improve their productivity and the quality of patient care, but also lowers our costs and improves our competitiveness. The IBM GMAS has helped us stay competitive and offer the leading edge technology that attracts top physicians to our staff and keeps patients feeling comfortable and well cared for."
Normally when you read or hear the term "grid", you might think of supercomputers, but in this case we are talking about information that is accessible from different interconnected locations. I've mentioned GMAS before in my posts [Blocks, Files and Content Addressable Storage and What Happened to CAS?] but I thought I would provide more detail on the elements of the solution.
Medical imaging equipment are called "modalities", which is just fancy hospital talk for "method of treatment".These have Ethernet connections designed to write to any storage with a CIFS or NFS interface. For example, press the button on the "X-ray" machine, and the digitized version of the X-ray is stored as a file to whatever NAS storage on the other end.
[Picture Archiving and Communication System] refer to the application and the computer equipment to manage these medical images, often stored in a DICOM format and indexed with HL7 metadata headers. There are many PACS vendors, GE Medical Systems, Siemens Medical, Agfa, Fuji, Philips, Kodak, Stentor, Emageon, Brit Systems, Mckesson, Amicus, Cerner, Medweb and Teramedica, to name a few. Many PACS providers embedded specific storage as part of their solution, but now are starting to realize that they need to be part of a larger storage infrastructure.
IBM System Storage [Multi-Level Grid Access Manager] is softwareon IBM System x servers that manages access across the grid of inter-connected hospitals, clinics and imaging facilities. It provides the NFS and CIFS interfaces to the modalities, and places the data into a GPFS file system on DS4000 series disk.
GPFS and DS4000 series disk
IBM [General Parallel File System] has all the Information Lifecycle Management (ILM) capabilities to move data from one disk storage level to another, automates deletion based on expiration date, and can provide concurrent access from multiple requesters.The IBM System Storage DS4000 series disk products can support both high-speed FC disk as well as low-cost SATA disk.For large medical images, the SATA disk is often a good fit. The advantage of GPFS is that you can have policies todecide which images are placed on FC disk, and which on SATA, and then later move these files based on access reference. Images that are accessed the most frequently can be on FC disk, and those that haven't been accessed in a while on SATA disk.
TSM space management
IBM [Tivoli Storage Manager for Space Management] supports moving files out of the GPFS file system and onto tape, based on policies. For example,keep the most recent 18 months on disk, and anything older than that gets moved to tape. This is similar to themigrate/recall technology used in DFSMShsm on the mainframe.
Tape Library automation
Before GMAS, paper and film images had to be retrieved manually from shelves and filing cabinets. The massive amountsof data being stored, and for such long periods of time, makes it impractical to store all of it on disk. With tape automation, any medical image more than 18 months old can be retrieved in minutes. Patients with an appointment can have all of their medical images retrieved in bulk the night before. Emergency room patients can have previous images retrieved while admission clerks check for insurance coverage and perform triage.
Images archived on the IBM GMAS are accessible in numerous ways. For example, all clinicians can access GMAS through hospital record system, which provides complete paperless and filmless access to the patient record including medical images, lab results, radiology reports, and pharmacy records. Medical workers at any location can also access the grid using their Web browsers. This allows each employee to use the display systems they are already familiar with.
Unlike disk-only based NAS systems, IBM's blended disk-and-tape approach makes this a much more cost-effective solution.For more details on IBM GMAS, read this 6-page[Frost & Sullivan whitepaper].
I am always amused in the manner the IT industry tries to solve problems. Take, for example, theprocess of backups. The simplest approach is to backup everything, and keep "n" versions of that.Simple enough for a small customer who has only a handful of machines, but does not scale well. Inmy post [Times a Million],I coined the phrase "laptop mentality", referring to people's inability to think through solutions in large scale.
Apparently, I am not alone.Steve Duplessie (ESG) wrote in his post[Random Thoughts]:
"I may even get to stop yelling at people to stop doing full backups every week on non-changing data (which is 80 %+) just because that's how they used to do it. They won't have a choice. You can't back up 5X your current data the way you do (or don't) today."
Hu Yoshida (HDS) does a great job explaining that thereare three ways to perform deduplication for backups:
Pre-processing. Have the backup software not backup unchanged data.
Inline processing. Have an index to filter the output of the backup as it sends data to storage.
Post-processing. Have the receiving storage detect duplicates and handle them accordingly.
"A full backup of 1TB data base tablespace is taken on day one. The next day another full backup is taken and only 2GB of that backup has any changes.
Using traditional full backup approaches after 2 nights, the backup capacity required is 2 x 1TB = 2TB
One method of calculating de-duplication ratios could yield a low ratio:
Total de-duplicated backup capacity used = 1TB + 2GB = 1.002TB
If the de-duplication ratio compares the amount of total physical storage used to the total amount that would have been used by traditional backup methods, the ratio = 2TB / 1.002TB = approximately 2:1
Another method of calculating de-duplication ratios could yield a high ratio:
Total de-duplicated backup capacity used still = 1.002TB
If the de-duplication ratio compares the amount of data stored in the most recent (second) backup to the amount that would have been used by traditional backup methods, the ratio 1TB / 2GB = 1000GB / 2GB = 500:1"
While IBM also offers deduplication in the IBM System Storage N series disk systems, I find that for backup, itis often more effective to apply best practices via IBM Tivoli Storage Manager (TSM). Let's take a look at some:
Exclude Operating System files
Why take full backups of your operating system every day? Yes, deduplication will find a lot to reduce fromthis, but best practices would exclude these. TSM has an include/exclude list, and the default version excludesall the operating system files that would be recovered from "bare machine recovery" or "new system install"procedures. Often, if the replacement machine has different gear inside, your OS backups aren't what you need,and a fresh OS install may determine this and install different drivers or different settings.
Exclude Application programs
Again, yes if there are several machines running the same application, you probably have opportunity for deduplication. However, unless you match these up with the appropriate registry or settings buried down in theoperating system, recovering just application program files may render an unusable system. Applications are bestinstalled from a common source that are either "pushed" through software distribution, or "pulled" from an application installation space.
If you have TB-sized databases, and are only doing full backups daily to protect it, have I got a solution for you.IBM and others have software that are "application-aware" and "database-aware" enough to determine what haschanged since the last backup and copy only that delta. Taking advantage of the TSM Application ProgrammingInterface (API) allows for both IBM and third party tools to take these delta backups correctly.
Which leaves us with user files, which are often unique enough on their own from the files of other users,that would not benefit from file-level deduplication. Backing up changed data only, as TSM does with its patented ["progressive incremental backup"] method, generally gets most of the benefits described by deduplication, without having to purchase storage hardware features.
Of course, if two or more users have identical files, the question might be why these are not stored on acommon file share. NAS file share repositories can greatly reduce each user keeping their own set of duplicates.It is interesting that some block-oriented deduplication,such as that found in the IBM System Storage N series, can get some benefit because some user files are oftenderivatives of other files, and there might be some 4 KB blocks of data in common.
Last November, I visited a customer in Canada. All of their problems were a direct result of taking full backupsevery weekend. It put a strain on their network; it used up too many disk and tape resources; and it took too long tocomplete. They asked about virtual tape libraries, deduplication, and anything else that could help them. The answer was simple: switch to IBM Tivoli Storage Manager and apply best practices.
My session was the first in the morning, at 8:30am, but managed to pack the room full of people. A few looklike they just rolled in from Brocade's special get-together in Casey's Irish Pub the night before.I presented how IBM's storage strategy for the information infrastructure fits into the greater corporate-wide themes.To liven things up, I gave out copies of my book[Inside System Storage: Volume I] to those who asked or answered the toughest questions.
Data Deduplication and IBM Tivoli Storage Manager (TSM)
IBM Toby Marek compared and contrasted the various data deduplication technologies and products available, andhow to deploy them as the repository for TSM workloads. She is a software engineer for our TSM software product,and gave a fair comparison between IBM System Storage N series Advanced Single Instance Storage (A-SIS), IBMDiligent, and other solutions out in the marketplace.If you are going to combine technologies, then it isbest to dedupe first, then compress, and finally encrypt the data. She also explained about the many cleverways that TSM does data reduction at the client side greatly reduces the bandwidth traffic over the LAN,as well as reducing disk and tape resources for storage. This includes progressive "incremental forever" backup for file selection, incremental backups for databases, and adaptive sub-file backup.Because of these data reduction techniques, you may not get as much benefit as deduplication vendors claim.
The Business Value of Energy Efficiency Data Centers
Scott Barielle did a great job presenting the issues related to the Green IT data center. He is part of IBM"STG Lab Services" team that does energy efficiency studies for customers. It is not unusual for his teamto find potential savings of up to 80 percent of the Watts consumed in a client's data center.
IBM has done a lot to make its products more energy efficient. For example, in the United States, most datacenters are supplied three-phase 480V AC current, but this is often stepped down to 208V or 110V with powerdistribution units (PDUs). IBM's equipment allows for direct connection to this 480V, eliminating the step-downloss. This is available for the IBM System z mainframe, the IBM System Storage DS8000disk system, and larger full-frame models of our POWER-based servers, and will probably be rolled out to someof our other offerings later this year. The end result saves 8 to 14 percent in energy costs.
Scott had some interesting statistics. Typical US data centers only spend about 9 percent of their IT budgeton power and cooling costs. The majority of clients that engage IBM for an energy efficiency study are not tryingto reduce their operational expenditures (OPEX), but have run out, or close to running out, of total kW ratingof their current facility, and have been turned down by their upper management to spend the average $20 million USDneeded to build a new one. The cost of electricity in the USA has risen very slowly over the past 35 years, andis more tied the to fluctuations of Natural Gas than it is to Oil prices.(a recent article in the Dallas News confirmed this:["As electricity rates go up, natural gas' high prices, deregulation blamed"])
Cognos v8 - Delivering Operational Business Intelligence (BI) on Mainframe
Mike Biere, author of the book [BusinessIntelligence for the Enterprise], presented Cognos v8 and how it is being deployed for the IBMSystem z mainframe. Typically, customers do their BI processing on distributed systems, but 70 percent of the world's business data is on mainframes, so it makes sense to do yourBI there as well. Cognos v8 runs on Linux for System z, connecting to z/OS via [Hypersockets].
There are a variety of other BI applications on the mainframe already, including DataQuant,AlphaBlox, IBI WebFocus and SAS Enterprise Business Intelligence. In addition to accessing traditional onlinetransaction processing (OLTP) repositories like DB2, IMS and VSAM, using the [IBM WebSphere ClassicFederation Server], Cognos v8 can also read Lotus databases.
Business Intelligence is traditionally query, reporting and online analytics process (OLAP) for the top 10 to 15 percent of the company, mostly executives andanalysts, for activities like business planning, budgeting and forecasting. Cognos PowerPlay stores numericaldata in an [OLAP cube] for faster processing.OLAP cubes are typically constructed with a batch cycle, using either "Extract, Transfer, Load" [ETL], or "Change Data Capture" [CDC], which playsto the strength of IBM System z mainframe batch processing capabilities.If you are not familiar with OLAP, Nigel Pendse has an article[What is OLAP?] for background information.
Over the past five years, BI is now being more andmore deployed for the rest of the company, knowledge workers tasked with doing day-to-day operations. Thisphenomenom is being called "Operational" Business Intelligence.
IBM Glen Corneau, who is on the Advanced Technical Support team for AIX and System p, presented the IBMGeneral Parellel File System (GPFS), which is available for AIX, Linux-x86 and Linux on POWER.Unfortunately, many of the questions were related to Scale Out File Services (SOFS), which my colleague GlennHechler was presenting in another room during this same time slot.
GPFS is now in its 11th release since its introducing in 1997. All of the IBM supercomputers on the [Top 500 list] use GPFS. The largest deployment of GPFS is 2241 nodes.A GPFS environment can support up to 256 file systems, each file system can have up to 2 billion filesacross 2 PB of storage. GPFS supports "Direct I/O" making it a great candidate for Oracle RAC deployments.Oracle 10g automatically detects if it is using GPFS, and sets the appropriate DIO bits in the stream totake advantage of GPFS features.
Glen also covered the many new features of GPFS, such as the ability to place data on different tiers ofstorage, with policies to move to lower tiers of storage, or delete after a certain time period, all conceptswe call Information Lifecycle Management. GPFS also supports access across multiple locations and offersa variety of choices for disaster recovery (DR) data replication.
Perhaps the only problem with conferences like this is that it can be an overwhelming["fire hose"] of information!