- Management Reference Guide
- Table of Contents
- Introduction
- Strategic Management
- Establishing Goals, Objectives, and Strategies
- Aligning IT Goals with Corporate Business Goals
- Utilizing Effective Planning Techniques
- Developing Worthwhile Mission Statements
- Developing Worthwhile Vision Statements
- Instituting Practical Corporate Values
- Budgeting Considerations in an IT Environment
- Introduction to Conducting an Effective SWOT Analysis
- IT Governance and Disaster Recovery, Part One
- IT Governance and Disaster Recovery, Part Two
- Customer Management
- Identifying Key External Customers
- Identifying Key Internal Customers
- Negotiating with Customers and Suppliers—Part 1: An Introduction
- Negotiating With Customers and Suppliers—Part 2: Reaching Agreement
- Negotiating and Managing Realistic Customer Expectations
- Service Management
- Identifying Key Services for Business Users
- Service-Level Agreements That Really Work
- How IT Evolved into a Service Organization
- FAQs About Systems Management (SM)
- FAQs About Availability (AV)
- FAQs About Performance and Tuning (PT)
- FAQs About Service Desk (SD)
- FAQs About Change Management (CM)
- FAQs About Configuration Management (CF)
- FAQs About Capacity Planning (CP)
- FAQs About Network Management
- FAQs About Storage Management (SM)
- FAQs About Production Acceptance (PA)
- FAQs About Release Management (RM)
- FAQs About Disaster Recovery (DR)
- FAQs About Business Continuity (BC)
- FAQs About Security (SE)
- FAQs About Service Level Management (SL)
- FAQs About Financial Management (FN)
- FAQs About Problem Management (PM)
- FAQs About Facilities Management (FM)
- Process Management
- Developing Robust Processes
- Establishing Mutually Beneficial Process Metrics
- Change Management—Part 1
- Change Management—Part 2
- Change Management—Part 3
- Audit Reconnaissance: Releasing Resources Through the IT Audit
- Problem Management
- Problem Management–Part 2: Process Design
- Problem Management–Part 3: Process Implementation
- Business Continuity Emergency Communications Plan
- Capacity Planning – Part One: Why It is Seldom Done Well
- Capacity Planning – Part Two: Developing a Capacity Planning Process
- Capacity Planning — Part Three: Benefits and Helpful Tips
- Capacity Planning – Part Four: Hidden Upgrade Costs and
- Improving Business Process Management, Part 1
- Improving Business Process Management, Part 2
- 20 Major Elements of Facilities Management
- Major Physical Exposures Common to a Data Center
- Evaluating the Physical Environment
- Nightmare Incidents with Disaster Recovery Plans
- Developing a Robust Configuration Management Process
- Developing a Robust Configuration Management Process – Part Two
- Automating a Robust Infrastructure Process
- Improving High Availability — Part One: Definitions and Terms
- Improving High Availability — Part Two: Definitions and Terms
- Improving High Availability — Part Three: The Seven R's of High Availability
- Improving High Availability — Part Four: Assessing an Availability Process
- Methods for Brainstorming and Prioritizing Requirements
- Introduction to Disk Storage Management — Part One
- Storage Management—Part Two: Performance
- Storage Management—Part Three: Reliability
- Storage Management—Part Four: Recoverability
- Twelve Traits of World-Class Infrastructures — Part One
- Twelve Traits of World-Class Infrastructures — Part Two
- Meeting Today's Cooling Challenges of Data Centers
- Strategic Security, Part One: Assessment
- Strategic Security, Part Two: Development
- Strategic Security, Part Three: Implementation
- Strategic Security, Part Four: ITIL Implications
- Production Acceptance Part One – Definition and Benefits
- Production Acceptance Part Two – Initial Steps
- Production Acceptance Part Three – Middle Steps
- Production Acceptance Part Four – Ongoing Steps
- Case Study: Planning a Service Desk Part One – Objectives
- Case Study: Planning a Service Desk Part Two – SWOT
- Case Study: Implementing an ITIL Service Desk – Part One
- Case Study: Implementing a Service Desk Part Two – Tool Selection
- Ethics, Scandals and Legislation
- Outsourcing in Response to Legislation
- Supplier Management
- Identifying Key External Suppliers
- Identifying Key Internal Suppliers
- Integrating the Four Key Elements of Good Customer Service
- Enhancing the Customer/Supplier Matrix
- Voice Over IP, Part One — What VoIP Is, and Is Not
- Voice Over IP, Part Two — Benefits, Cost Savings and Features of VoIP
- Application Management
- Production Acceptance
- Distinguishing New Applications from New Versions of Existing Applications
- Assessing a Production Acceptance Process
- Effective Use of a Software Development Life Cycle
- The Role of Project Management in SDLC— Part 2
- Communication in Project Management – Part One: Barriers to Effective Communication
- Communication in Project Management – Part Two: Examples of Effective Communication
- Safeguarding Personal Information in the Workplace: A Case Study
- Combating the Year-end Budget Blitz—Part 1: Building a Manageable Schedule
- Combating the Year-end Budget Blitz—Part 2: Tracking and Reporting Availability
- References
- Developing an ITIL Feasibility Analysis
- Organization and Personnel Management
- Optimizing IT Organizational Structures
- Factors That Influence Restructuring Decisions
- Alternative Locations for the Help Desk
- Alternative Locations for Database Administration
- Alternative Locations for Network Operations
- Alternative Locations for Web Design
- Alternative Locations for Risk Management
- Alternative Locations for Systems Management
- Practical Tips To Retaining Key Personnel
- Benefits and Drawbacks of Using IT Consultants and Contractors
- Deciding Between the Use of Contractors versus Consultants
- Managing Employee Skill Sets and Skill Levels
- Assessing Skill Levels of Current Onboard Staff
- Recruiting Infrastructure Staff from the Outside
- Selecting the Most Qualified Candidate
- 7 Tips for Managing the Use of Mobile Devices
- Useful Websites for IT Managers
- References
- Automating Robust Processes
- Evaluating Process Documentation — Part One: Quality and Value
- Evaluating Process Documentation — Part Two: Benefits and Use of a Quality-Value Matrix
- When Should You Integrate or Segregate Service Desks?
- Five Instructive Ideas for Interviewing
- Eight Surefire Tips to Use When Being Interviewed
- 12 Helpful Hints To Make Meetings More Productive
- Eight Uncommon Tips To Improve Your Writing
- Ten Helpful Tips To Improve Fire Drills
- Sorting Out Today’s Various Training Options
- Business Ethics and Corporate Scandals – Part 1
- Business Ethics and Corporate Scandals – Part 2
- 12 Tips for More Effective Emails
- Management Communication: Back to the Basics, Part One
- Management Communication: Back to the Basics, Part Two
- Management Communication: Back to the Basics, Part Three
- Asset Management
- Managing Hardware Inventories
- Introduction to Hardware Inventories
- Processes To Manage Hardware Inventories
- Use of a Hardware Inventory Database
- References
- Managing Software Inventories
- Business Continuity Management
- Ten Lessons Learned from Real-Life Disasters
- Ten Lessons Learned From Real-Life Disasters, Part 2
- Differences Between Disaster Recovery and Business Continuity , Part 1
- Differences Between Disaster Recovery and Business Continuity , Part 2
- 15 Common Terms and Definitions of Business Continuity
- The Federal Government’s Role in Disaster Recovery
- The 12 Common Mistakes That Cause BIAs To Fail—Part 1
- The 12 Common Mistakes That Cause BIAs To Fail—Part 2
- The 12 Common Mistakes That Cause BIAs To Fail—Part 3
- The 12 Common Mistakes That Cause BIAs To Fail—Part 4
- Conducting an Effective Table Top Exercise (TTE) — Part 1
- Conducting an Effective Table Top Exercise (TTE) — Part 2
- Conducting an Effective Table Top Exercise (TTE) — Part 3
- Conducting an Effective Table Top Exercise (TTE) — Part 4
- The 13 Cardinal Steps for Implementing a Business Continuity Program — Part One
- The 13 Cardinal Steps for Implementing a Business Continuity Program — Part Two
- The 13 Cardinal Steps for Implementing a Business Continuity Program — Part Three
- The 13 Cardinal Steps for Implementing a Business Continuity Program — Part Four
- The Information Technology Infrastructure Library (ITIL)
- The Origins of ITIL
- The Foundation of ITIL: Service Management
- Five Reasons for Revising ITIL
- The Relationship of Service Delivery and Service Support to All of ITIL
- Ten Common Myths About Implementing ITIL, Part One
- Ten Common Myths About Implementing ITIL, Part Two
- Characteristics of ITIL Version 3
- Ten Benefits of itSMF and its IIL Pocket Guide
- Translating the Goals of the ITIL Service Delivery Processes
- Translating the Goals of the ITIL Service Support Processes
- Elements of ITIL Least Understood, Part One: Service Delivery Processes
- Case Study: Recovery Reactions to a Renegade Rodent
- Elements of ITIL Least Understood, Part Two: Service Support
- Case Studies
- Case Study — Preparing for Hurricane Charley
- Case Study — The Linux Decision
- Case Study — Production Acceptance at an Aerospace Firm
- Case Study — Production Acceptance at a Defense Contractor
- Case Study — Evaluating Mainframe Processes
- Case Study — Evaluating Recovery Sites, Part One: Quantitative Comparisons/Natural Disasters
- Case Study — Evaluating Recovery Sites, Part Two: Quantitative Comparisons/Man-made Disasters
- Case Study — Evaluating Recovery Sites, Part Three: Qualitative Comparisons
- Case Study — Evaluating Recovery Sites, Part Four: Take-Aways
- Disaster Recovery Test Case Study Part One: Planning
- Disaster Recovery Test Case Study Part Two: Planning and Walk-Through
- Disaster Recovery Test Case Study Part Three: Execution
- Disaster Recovery Test Case Study Part Four: Follow-Up
- Assessing the Robustness of a Vendor’s Data Center, Part One: Qualitative Measures
- Assessing the Robustness of a Vendor’s Data Center, Part Two: Quantitative Measures
- Case Study: Lessons Learned from a World-Wide Disaster Recovery Exercise, Part One: What Did the Team Do Well
- (d) Case Study: Lessons Learned from a World-Wide Disaster Recovery Exercise, Part Two
There are a variety of considerations that come into play when configuring infrastructure storage for optimal performance. Figure 1 lists some of the most common of these. I will start with performance considerations at the processor side and work my way out to the storage devices.
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Figure 1 Storage Management Performance Considerations
The first performance consideration is the size and type of main memory. Processors of all kinds—from desktops up to mainframes—have their performance impacted by the amount of main storage installed in them. The amount can vary from just a few hundred megabytes for desktops up to tens of gigabytes for mainframes. Computer chip configurations, particularly for servers, also vary from one to tens of gigabyte memory chips. The density can influence the total amount of memory that can be installed in a server due to the limitation of physical memory slots.
In smaller shops, systems administrators responsible for server software may also configure and manage main storage. In larger shops, disk storage analysts will likely interact with systems administrators to configure the entire storage environment, including main memory, for optimal performance. These two groups of analysts also normally confer about buffers, swap space, and channels. The number and size of buffers are calculated to maximize data transfer rates between host processors and external disk units without wasting valuable storage and cycles within the processor. Similarly, swap space is sized to minimize processing time by providing the proper ratio of real memory space to disk space. A good rule of thumb for this ratio used to be to size the swap space to be equal to that of main memory, but today this will vary depending on applications and platforms.
Channels connecting host processors to disk and tape storage devices will vary as to their transfer speed, their technology, and the maximum number able to be attached to different platforms. The number and speed of the channels influence performance, response, throughput, and costs. All of these factors should be considered by storage management specialists when designing an infrastructure's channel configurations.
Tape and disk controllers have variable numbers of input channels attaching them to their host processors, as well as variable numbers of devices attaching to their output ports. Analysis needs to be done to determine the correct number of input channels and output devices per controller to maximize performance while still staying within reasonable costs. There are several software analysis tools available to assist in this, and often it is the hardware suppliers who can offer the greatest assistance.
A software methodology called a logical volume group assembles together two or more physical disk volumes into one logical grouping for performance reasons. This is most commonly done on huge disk array units housing large databases or data warehouses. The mapping of physical units into logical groupings is a nontrivial task that almost always warrants the assistance of performance specialists from the hardware supplier or other sources.
To improve performance of disk transactions, huge disk arrays also have varying sizes of cache memory. Large database applications benefit most from utilizing a very fast—and very expensive—high-speed cache. Because of the expense of the cache, disk storage specialists endeavor to tune the databases and the applications to make maximum use of the cache,with the goal being to have the most frequently accessed parts of the database residing in the cache. Sophisticated pre-fetch algorithms determine which data is likely to be requested next and then initiate the preloading of it into the cache. The effectiveness of these algorithms greatly influences the speed and performance of the cache. Since the cache is read first for all disk transactions, finding the desired piece of data in the cache—i.e., a hit—greatly improves response times by eliminating the relatively slow data transfer from physical disks. Hit ratios (hits versus misses) between 85% and 95% are not uncommon for well-tuned databases and applications; this high hit ratio helps to justify the cost of the cache.
Two more recent developments in configuring storage systems for optimal performance are storage area networks (SAN) and network attached storage (NAS). SAN is a configuration enhancement that places a high-speed fiber-optic switch between servers and disk arrays. The two primary advantages are speed and flexibility. These advantages do not come cheap. Disk arrays and high speed switches can costs tens of millions of dollars, but the performance, reliability and recoverability of this type of configuration often warrant it.
A less costly alternative to SAN is the NAS which is similar in concept to SAN except that the switch in NAS is replaced by a network. This enables data to be shared between storage devices and processors across a network. The speed and performance of a NAS is not on a par with a SAN but neither is it costs.
One of the important points to take away form this discussion of storage management is that effective performance of storage requires a holistic point of view. Optimal performance of mainframe storage, server storage, and disk and tape storage does not happen independent of each other. All of these components need to be tuned and balanced to support each other I order to deliver the best possible response times. This can only be achieved by considering all of these elements together.
In part three of this series I discuss the important characteristic of storage management reliability.