WebSphere Application Server V8 New Features and a primer on WAS V8.5

Transcription

1 WebSphere Application Server V8 New Features and a primer on WAS V8.5 Lalitha V Pannala, Development Manager, WebSphere India Software Lab, IBM

2 Important Disclaimers THE INFORMATION CONTAINED IN THIS PRESENTATION IS PROVIDED FOR INFORMATIONAL PURPOSES ONLY. WHILST EFFORTS WERE MADE TO VERIFY THE COMPLETENESS AND ACCURACY OF THE INFORMATION CONTAINED IN THIS PRESENTATION, IT IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. ALL PERFORMANCE DATA INCLUDED IN THIS PRESENTATION HAVE BEEN GATHERED IN A CONTROLLED ENVIRONMENT. YOUR OWN TEST RESULTS MAY VARY BASED ON HARDWARE, SOFTWARE OR INFRASTRUCTURE DIFFERENCES. ALL DATA INCLUDED IN THIS PRESENTATION ARE MEANT TO BE USED ONLY AS A GUIDE. IN ADDITION, THE INFORMATION CONTAINED IN THIS PRESENTATION IS BASED ON IBM S CURRENT PRODUCT PLANS AND STRATEGY, WHICH ARE SUBJECT TO CHANGE BY IBM, WITHOUT NOTICE. IBM AND ITS AFFILIATED COMPANIES SHALL NOT BE RESPONSIBLE FOR ANY DAMAGES ARISING OUT OF THE USE OF, OR OTHERWISE RELATED TO, THIS PRESENTATION OR ANY OTHER DOCUMENTATION. NOTHING CONTAINED IN THIS PRESENTATION IS INTENDED TO, OR SHALL HAVE THE EFFECT OF: - CREATING ANY WARRANT OR REPRESENTATION FROM IBM, ITS AFFILIATED COMPANIES OR ITS OR THEIR SUPPLIERS AND/OR LICENSORS 2

3 Agenda WebSphere Application Server - Evolution Brief WAS v8 Key New Features Speed Delivery of Applications and Services Operational Efficiency and Reliability Security and Control WAS v8.5 Liberty A Primer 3

4 WebSphere Application Server: Over a Decade of Leadership & Trusted Delivery WebSphere Application Server V6.1 WebSphere Application Server V6.0.2 WebSphere Application Server V6 WebSphere Application Server V6.1 Feature Packs (FEP) WebSphere Application Server V7 WAS V7 & V6.1 Feature Packs WAS V7 Feature Packs (XML, CEA, SCA) WAS HV WAS V8 Web 2.0 & Mobile FEP WAS HV Refresh Migration Toolkit Refresh 2010 WAS V8 Alpha, Beta & Beta Refresh WAS V7 Feature Packs OSGi Apps & JPA 2.0 CEA Mobile Widgets Dynamic Scripting WAS HV Refresh Migration Toolkit Refresh

5 WAS v8 Key New Features 5

6 Intelligently Manage Application Environments & Deliver Rich User Experiences Faster Speed Delivery of Applications & Services Operational Efficiency & Reliability Security & Control Open Source to Enterprise Free WAS for Developers Self Service Development Environments Programming Models Java TM EE 6 Web 2.0 & Mobile OSGi Applications JPA SCA CEA Dynamic Scripting Integrated Tooling Application Adapters High Performance Install & Maintenance Transactional Strength Scalability & HA Problem Determination Platform & Environment Flexibility Feature Packs Administrative Productivity Metrics ITCAM for WAS Application Migration Toolkit Continued mixed cell support Configuration Migration Tooling 6 * Java is the registered trademark of Oracle Corp

7 Intelligently Manage Application Environments & Deliver Rich User Experiences Faster Speed Delivery of Applications & Services Operational Efficiency & Reliability Security & Control Open Source to Enterprise Free WAS for Developers Self Service Development Environments Programming Models Java EE 6 Web 2.0 & Mobile OSGi Applications JPA SCA CEA Dynamic Scripting Integrated Tooling Application Adapters High Performance Install & Maintenance Transactional Strength Scalability & HA Problem Determination Platform & Environment Flexibility Feature Packs Administrative Productivity Metrics ITCAM for WAS Application Migration Toolkit Continued mixed cell support Configuration Migration Tooling 7

8 8 Enabling Developers to Start With Open Source/Community Software & Benefit from IBM Value Add in Production Apache Aries 8

9 Lowering Barriers to Developer Adoption No charge WebSphere Application Server for Developers For use on developer desktop at no charge Download at: 9

10 Speed the Development & Test Lifecycle Through Self Service Access to Repeatable Environments IBM Workload Deployer & WAS Hypervisor Edition 1 Self service request Developer 2 Rapidly access consistent & repeatable provisioned development & test environment 10

11 Monitored Directory Support Accelerate edit-compile-debug tasks during the development lifecycle Enhanced developer productivity through new monitored directorybased application install, update and uninstall of Java EE applications Drag & drop and command line support Supported with WAS Express, Base, ND & z/os Supported file types: EAR (Enterprise Archive) WAR (Web Application Archive) JAR (Java Archive) SAR (SIP Application Resource) 11

12 Develop Innovative Applications Faster A Broad Set of Integrated Standards-Based Programming Models With WAS V6.1 & 7.0 Dynamic Scripting EJB 3.0 Web 2.0 Web Services Web 2.0 CEA XML SCA OSGi Apps & JPA 2.0 Java Batch J2EE 1.4 WAS V6.1 EJB 3.0 Web Services Java EE 5 WAS V7 With WAS V8 Web 2.0 & Mobile Dynamic Scripting CEA XML SCA OSGi Apps & JPA 2.0 Java Batch Java EE 6 WAS V8 2Q 2011 delivery 12

13 Java EE 6 Simplify standards-based enterprise Java development for dept. to core business apps Enhanced developer productivity, user experiences, performance & integration: Enterprise JavaBeans (EJB) 3.1: Enhanced developer productivity through simplification including testing outside of the application server, new timer support & async enhancements Java Persistence API (JPA) 2.0: Enhanced developer ease of use & app performance through embeddables, improved locking, & dynamic query construction JavaServer Faces (JSF) 2.0: Enhanced developer productivity & end user experience through annotations Java API for RESTful Web Services (JAX-RS) 1.1: Deliver better user experiences faster through integrated Web 2.0 prog model support Java Architecture for XML Binding (JAXB) 2.2: Improved performance via new default marshalling optimizations Enterprise Web Services 1.3: Improved integration and reuse support Java API for XML-Based Web Services (JAX-WS) 2.2: Developer productivity and security enhancements 13

14 OSGi Applications Feature Pack Modularization in Java Problems with Jars 14 No jar scoped access modifiers No means for a jar to declare its dependencies No versioning Across apps - each archive typically contains all the libraries required by the application Common libraries/frameworks get installed with each application Multiple copies of libraries in memory Package Class Class Class Package Class Class Class weba.war weba.war WEB-INF/classes/servletA.class WEB-INF/classes/servletA.class WEB-INF/lib/spring.jar WEB-INF/lib/spring.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/junit.jar WEB-INF/lib/junit.jar webb.war webb.war WEB-INF/classes/servletB.class WEB-INF/classes/servletB.class WEB-INF/lib/spring.jar WEB-INF/lib/spring.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/junit.jar WEB-INF/lib/junit.jar webc.war webc.war WEB-INF/classes/servletC.class WEB-INF/classes/servletC.class WEB-INF/lib/spring.jar WEB-INF/lib/spring.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/junit.jar WEB-INF/lib/junit.jar 1

15 OSGi Bundles and Class Loading OSGi Bundle A jar containing: Classes and resources OSGi Bundle manifest. What s in the manifest: - Bundle-Version: Multiple versions of bundles can live concurrently - Import-Package: What packages from other bundles does this bundle depend upon? - Export-Package: What packages from this bundle are visible and reusable outside of the bundle? Class Loading Each bundle has its own loader. No flat or monolithic classpath. Class sharing and visibility decided by declarative dependencies, not by class loader hierarchies. OSGi framework works out the dependencies including versions. Manifest-Version: 1.0 Bundle-ManifestVersion: 2 Bundle-Name: MyService bundle Bundle-SymbolicName: com.sample.myservice Bundle-Version: Bundle-Activator: com.sample.myservice.activator Import-Package: com.something.i.need;version="1.1.2" Export-Package: com.myservice.api;version="1.0.0" 15

16 OSGi Enterprise Specification Apache Aries created as a new Apache incubator project in Sep 2009: to provide enterprise OSGi spec implementations Aries componentry supporting an enterprise OSGi programming model are being integrated into both Geronimo and WAS Application-level exploitation is introduced in the WebSphere Application Server V7 Feature Pack for OSGi Applications and Java Persistence API (JPA) Generally available May

17 Getting Started: Bundlizing vanilla JEE No Java code changes; war modules -> bundles Common, bundles may be easily factored out of the WARs and used at specific versions weba.war weba.war WEB-INF/classes/servletA.class WEB-INF/classes/servletA.class WEB-INF/lib/json4j.jar WEB-INF/lib/json4j.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/junit.jar WEB-INF/lib/junit.jar webb.war webb.war WEB-INF/classes/servletB.class WEB-INF/classes/servletB.class WEB-INF/lib/json4j.jar WEB-INF/lib/json4j.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/junit.jar WEB-INF/lib/junit.jar webc.war webc.war WEB-INF/classes/servletC.class WEB-INF/classes/servletC.class WEB-INF/lib/json4j.jar WEB-INF/lib/json4j.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/commons-logging.jar WEB-INF/lib/junit.jar WEB-INF/lib/junit.jar weba.wab weba.wab WEB-INF/classes/servletA.class WEB-INF/classes/servletA.class META-INF/MANIFEST.MF META-INF/MANIFEST.MF webb.wab webb.wab WEB-INF/classes/servletB.class WEB-INF/classes/servletB.class META-INF/MANIFEST.MF META-INF/MANIFEST.MF webc.wab webc.wab WEB-INF/classes/servletC.class WEB-INF/classes/servletC.class META-INF/MANIFEST.MF META-INF/MANIFEST.MF Import-Package Bundle Repository Bundle Repository WEB-INF/lib/json4j.jar;version= a.b.c WEB-INF/lib/json4j.jar;version= a.b.c WEB-INF/lib/commons-logging.jar;version= WEB-INF/lib/commons-logging.jar;version= WEB-INF/lib/junit.jar WEB-INF/lib/junit.jar 17

18 New: Bundle Repository Config in WAS 18

19 Blueprint Components and Services publishes service dependencies injected consumes service A static assembly and configuration of components (POJOs) OSGI-INF/blueprint/ blueprint.xml Blueprint bundle Specifies a Dependency Injection container, standardizing established Spring conventions Configuration and dependencies declared in XML module blueprint, which is a standardization of Spring application context XML. Extended for OSGi: publishes and consumes components as OSGi services Simplifies unit test outside either Java EE or OSGi r/t. The Blueprint DI container is a part of the server runtime (compared to the Spring container which is part of the application.) 19

20 OSGi Service Registry and JNDI OSGi services are published to and looked up from OSGi service registry. From declarations in Blueprint XML Simplify integrating with existing JEE components: OSGi Services registered in the OSGi Service Registry are also available in JNDI via the osgi:service URL scheme Administered resources bound to JNDI are also published as services in the OSGi Service Registry. The JNDI name is published as a service property called osgi.jndi.service.name 20

21 New: Enterprise Bundle Archive (EBA) An isolated, cohesive application consisting of a collection of bundles, is deployed as a logical unit in a.eba archive An OSGi Application. Constituent bundles may be contained or referenced from a bundle repository. Services provided by the application are isolated to the application unless explicitly exposed through EBA-level application manifest Config by exception - absence of APPLICATION.MF means: application content is the set of bundles contained by-value plus any repository-hosted dependencies identified during deployment. Bundle Bundle Repository Repository json4j.jar Application Manifest Enumerates constituent bundles Declares Application externals blog.eba blog-persistence.jar blog.jar blog-servlet.jar 21

22 Web 2.0 & Mobile FeaturePack v Extend the reach of enterprise web applications across devices to deliver high quality user experiences Enabling Mobile UI s: Based on industry-accepted technologies, including Dojo Toolkit & Widget Infrastructure, Asynchronous JavaScript and XML (Ajax), Representational State Transfer (REST) Web services, and Apache Wink. Component updates: Dojo Toolkit 1.6, JAX-RS New Mobile Widget Library Common Mobile & RIA Building Blocks: Directory Listing Service File Upload Service (multipart) Graphics Conversion Service (SVG/PNG/JPG/PDF) Available as a Feature Pack supporting WAS v8, v7 & v6.1 22

23 JPA Persistence Feature Support An example Types Entities Entities are Plain Old Java Objects (POJOs) public class Customer implements Serializable { Key Attributes annotated fields and key annotation can be used to signify a (name="order_id") public Integer getorderid() { return id; } 23

24 Communications Enabled Applications (CEA) Integrated! Simply and rapidly add communications capabilities, like Click to Call and Cobrowsing, to any Web application leveraging existing skills and an SOA approach Key Features: Simplicity: 3 lines of code to add CEA into web app Mobile Browser Widgets: Enable native look & feel Telephony Access: REST & Web service interfaces to Make call, disconnect call & incoming call notifications Web 2.0 Widgets: Customizable & extensible with Web 2.0 widgets Click to Call Call Notifications Collaboration Dialog Contact Center Cobrowsing Peer to Peer Cobrowsing Two-way Synchronized Forms PoC Friendly: Unit test environment & pre-tested with Cisco & Nortel unified communications products Shopper s friend Shopper Contact Center Rep Peer to Peer Cobrowsing Click to Call Contact Center Cobrowsing Two-way Synchronized Forms 24

25 Dynamic Scripting Leverage existing platform investment to rapidly address situational application requirements using PHP or Groovy Key Features: Time to Value: Rapid development with PHP, Groovy, and a Web 2.0 oriented programming model based on WebSphere smash Reuse: Develop and deploy application components supporting the iwidget specification that can be incorporated into WebSphere Portal and IBM Mashup Center-based applications Web 2.0 REST, RSS / ATOM Available as a Feature Pack supporting WAS v8, v7 & v6.1 25

26 Integrated Tooling Support Through Rational Application Developer (RAD) Web 2.0 & Mobile Extend SOA and Java EE assets to the glass & mobile devices via dynamic, rich JSF, DOJO & mobile web applications Refine Refactor RAD / OSGi Build dynamic, modular, and easily manageable applications SOA Assemble Web services and SCA components into heterogeneous business applications Code Deploy Debug WAS Test Java EE 6 Develop and test Java EE 6 applications with annotation based programming WAS Integration Hot deploy incremental changes to WAS Modern Batch Integrated programming model support for batch applications 26

27 Application Adapters Enhance reuse and extend application asset life IBM WebSphere Adapters 7.5 includes enhanced adapters for: SAP Software Siebel Business Applications Oracle E-Business Suite JD Edwards EnterpriseOne PeopleSoft Enterprise Supported for development & test with WebSphere Application Server as part of WAS V8 license Production usage requires separate WebSphere Adapters license 27

28 Intelligently Manage Application Environments & Deliver Rich User Experiences Faster Speed Delivery of Applications & Services Operational Efficiency & Reliability Security & Control Open Source to Enterprise Free WAS for Developers Self Service Development Environments Faster Edit-Compile-Debug Programming Models Java EE 6 Web 2.0 & Mobile OSGi Applications JPA SCA CEA Dynamic Scripting Integrated Tooling Application Adapters High Performance Install & Maintenance Transactional Strength Scalability & HA Problem Determination Platform & Environment Flexibility Feature Packs Administrative Productivity Metrics ITCAM for WAS Application Migration Toolkit Continued mixed cell support Configuration Migration Tooling 28

29 2 9 IBM WebSphere Application Server A Smarter Choice Lower TCO WebSphere Application Server ND has up to 49% total cost of ownership advantage over JBoss (1) 1. Based on IBM WebSphere Application Server V7 vs.jboss Enterprise Application Platform V5 TCO Analysis study conducted by Summa Technologies and funded by IBM in Dec TCO advantage calculations are for medium environments comparing IBM WebSphere Application Server Network Deployment V7 (WAS ND) with JBoss Enterprise Application Platform V5 (JBoss EAP) 29

30 IBM WebSphere Application Server A Smarter Choice Better Performance IBM is the industry leader in EjOPS/core performance (1) IBM is the industry leader in single node performance (2) IBM: 16,646 EjOPS/core JBoss has not published a single performance result (3) Footnotes: 1. Results based on SPECjEnterprise2010 benchmark from as of 07/07/2011 were used in this comparison. Comparing WebSphere Application Server V8 on IBM HS Blade Server HS22 X5690 result of EjOPS/core (3, EjOPS, 12 cores, 2 chips) 2. Results based on SPECjEnterprise2010 benchmark from as of 07/07/2011 were used in this comparison: Comparing WebSphere Application Server V7 on IBM Power 780 Express result of 16, EjOPS on 64 cores,8 chips 3. Based on publically available information as of 07/07/

31 Centralized Installation Manager (CIM) Faster time to value & lower operational costs through new install & maintenance tech. CIM V8 is available from Job Manager & DManager Job Manager based solution spans the boundaries of the cell Install targets are specified in agentless fashion Install and config job scheduling is supported CIM V8 is able to remotely install WebSphere Application Server, IBM HTTP Server, Application Clients and Web Server Plug-ins Better scalability due to more distributed architecture CIM V7 function is still available with Deployment Manager along with new CIM V8 function Centralized Installation Manager IIM Install Kit: Response File Install jobs Inventory info IIM Repository Binary payload IIM Target Separation between Job Manager, Target Hosts and IIM repositories 31

32 Intelligently Manage Application Environments & Deliver Rich User Experiences Faster Speed Delivery of Applications & Services Operational Efficiency & Reliability Security & Control Open Source to Enterprise Free WAS for Developers Self Service Development Environments Faster Edit-Compile-Debug Programming Models Java EE 6 Web 2.0 & Mobile OSGi Applications JPA SCA CEA Dynamic Scripting Integrated Tooling Application Adapters High Performance Install & Maintenance Transactional Strength Scalability & HA Problem Determination Platform & Environment Flexibility Feature Packs Administrative Productivity Metrics ITCAM for WAS Application Migration Toolkit Continued mixed cell support Configuration Migration Tooling 32

33 Flexible Management Utilize a flexible, scalable and asynchronous administrative topology for highly productive global administration and management Admin Agent Centralized Node Administration Job Manager Asynchronous Remote Management Multiple Admin Agents and/or Deployment Mgrs Highly Scalable Admin Agent WAS Server Admin Agent WAS Servers Admin Agent WAS Express Server Job Manager Deployment Manager Server Server Server Server Server WAS Network Deployment Cell Deployment Manager Server Server Server Server Server Server WAS Network Deployment Cell 33

34 Continued Mixed Version Cell Support Support for existing infrastructure in new V8 deployments to save time, money and reduce risk WAS Network Deployment V8 Cell V8 Deployment Manager Node Agent Node Agent Node Agent ND V8.0 Nodes ND V6.1 Nodes ND V7.0 Nodes V8 Cell can contain & 8.0 nodes 34

35 3 5 Application Migration Tooling Migrate applications from WebSphere & other Java EE application servers to WebSphere faster with minimized risk Migrate applications from older releases to WAS V8 or V7 Migrate from Oracle or JBoss faster and easier to WAS V8 or V7 Migrate applications up to 2x as fast Migrate web services up to 3x as fast Application Migration Tools Analyzes source code to find potential migration problems: Removed features Deprecated features Behavior changes JRE 5 & JRE 6 differences Java EE specification changes or enforcements Capable of making some application changes Provides guidance on how to make required changes Works with Eclipse or Rational Application Developer (RAD) WAS V7.0, V6.0 & 6.1 V5.1 Oracle WLS AMT Oracle AS WebSphere Application Server V8, V7 JBoss AS / EAP 35 Get the Tool at No Charge:

36 Configuration Migration Tooling Migrate WebSphere environments faster with minimized risk Assists administrators in moving their configuration when migrating Merges old configuration with new configuration Especially useful for customers that have large topologies Large telecom customer recently used the tool when migrating a 500+ JVM environment Provides a framework for Stack product migration Already in use by Commerce, Portal, WPS and Virtual Enterprise v6.x, v7.0 Profile WASPreUpgrade Backup Files Server Configuration Applications Resources Create V8.0 Profile V8.0 Profile WASPostUpgrade Migrated V8.0 Profile 36

37 WAS v8.5 Liberty A Primer 37

38 Introducing WAS v8.5 A Primer WAS v8.5 Alpha and the Liberty Profile What it Means to Developers Tooling Summary Demo and Discussion 38

39 Developer Feedback Developers are looking for more (or less) from the test server runtime in the tools. Greater test simplicity Config model (hard to edit, backup, share) Admin console is for operational mgmt rather than development Problem determination (including within customer apps) Responsiveness Primarily incremental publishing, app install, server startup time Footprint WAS server types defined to RAD have a WAS production server footprint and memory use. For all types of application 39

40 Frequency of Development Tasks Common development tasks include: Hourly Daily Weekly Monthly Modify file within an application Debug a problem in an application Restart/redeploy application Restart server Share code with team Change app structure (add/remove a module/bundle) Make config change Share config change with team Reproduce problem from another environment Upgrade to new service release Create application Install server fastest faster fast Frequency Time to complete All tasks should be as painless as possible, with special emphasis on the more frequent ones. If the time taken to accomplish these tasks is an impediment to the development, the cost of the fidelity of the test server runtime is challenged. 40

41 Oct Fall Launch: WAS V8.5 Alpha - Introducing WAS Liberty Profile Not a single static profile: rather a dynamic, flexible profile of the runtime to load only what the application needs Memory footprint (web feature): < 50 MB Profile is dynamic - switch parts of the server on & off w/out restart Extremely lightweight Incredibly fast (re)start times: <5 seconds Fidelity with full-profile WAS Same containers, QoS as full-profile WAS But radically refactored to focus on the development experience Initially focused on dev/test of web, mobile and OSGi apps. Simplified configuration for quick time to productivity; one single config file or modular config (as desired) Easy to share / diff / manage in version control Tools available as Eclipse features as well as in RAD Visit and participate in the new WAS Developer Community ibm.com/wasdev 41

42 Initial feature set Alpha (available now) servlet-3.0 jsp-2.2 jsf-2.0 jpa-2.0 jdbc-4.0 ssl-1.0 jmx-1.0 webappsecurity (more to come) Beta 1 (target Dec 2011) Beta 2 (target Mar 2012) 42

43 Summary: Flexible, Lightweight Profile An extremely lightweight WAS profile for web apps Incredibly fast (re)start times: <5 seconds Flexible configuration to load only what the application needs Memory footprint (web feature): < 50 MB Simplified configuration for quick time to productivity; single config file across dev environments (if desired) Free & frictionless download for development: including ZIP developer install from WAS for Dev download site Ability to build web apps with standard Eclipse Tools: Eclipse plugin included for broad tooling support Fidelity with full profile WAS server Flexibility of development platforms and JDKs Simplified configuration will ease migration 43

44 Get Started Now! Download WebSphere Application Server for Developers at NO CHARGE For use on developer desktop Download at: 44

45 Learn More About Websphere Application Server v8 and Dynamic Application Infrastructure! WebSphere Application Server v8 ibm.com/appfoundation Application Foundation ibm.com/appfoundation Intelligent Management ibm.com/intellmgmt Extreme Transaction Processing ibm.com/xtp DataPower XC10 Overviewibm.com/appinfrastructure

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48 Copyright and Trademarks IBM Corporation All Rights Reserved. IBM, the IBM logo, and ibm.com are trademarks or registered trademarks of International Business Machines Corp., and registered in many jurisdictions worldwide. Other product and service names might be trademarks of IBM or other companies. A current list of IBM trademarks is available on the Web see the IBM Copyright and trademark information page at URL: 48

49 Performance - Disclaimer Based on measurements and projections using standard IBM benchmarks in a controlled environment. The actual throughput that any user will experience will vary depending upon considerations such as the amount of multiprogramming in the user's job stream, the I/O configuration, the storage configuration, and the workload processed. Therefore, no assurance can be given that an individual user will achieve throughput improvements equivalent to the performance ratios stated here. 49