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  OS/2 Warp 4 Capacity Planning and Performance Tuning Guide Document Number: WARP4TTT December 5, 1996 Personal Software Products Duc J. Vianney, Ph. D., Senior Programmer OS/2 External Performance, Austin, TX Tony White, OS/2 Performance Consultant Personal Systems Solutions Center, Dallas, TX Preface This paper was produced to assist you in improving the performance of your OS/2 system by providing information on OS/2 Warp 4, its various subsystems, and practical performance tuning tips and techniques. It begins by familiarizing you the new features and enhanced functions of OS/2 Warp 4. It will then introduce you to the concepts and terminology needed to successfully tune an OS/2 system. You will learn to recognize the symptoms of many common performance problems. You will also learn how to create and use a repeatable process for analyzing a system's performance problem and understand the many tuning parameters and techniques used to fully optimize your system. The tuning tips and techniques are divided into 3 sections targeted to different levels of complexity: basic OS/2 tuning, advanced OS/2 tuning, and tuning tips for a networked OS/2 workstation. This paper documents the procedures used and knowledge obtained from performance evaluation and measurement activities. Some procedures have been recorded in documents previously published by OS/2 development and support groups within IBM. It should be considered a working document subject to forthcoming changes without notice as additional information is obtained. The information contained in this paper represents the interpretation of IBM on the issues discussed based on the measurement results as of the date of publication. Since the results are applicable only to the system under test, IBM makes no commitment nor guarantees the accuracy of any data measured after the date of publication. The authors wish to express their sincere thanks to the comments, suggestions and reviews made by Michael Martino, Cyndi Kubich, Rich Wahl, Robert Paulsen, Jimmy DeWitt, Ivan Eisen, Bob Russell, Steve Woodward, Lannes Robinson, Valerie Jackson, and many others that have involved with OS/2 Warp products. For further references, please refer to the following documents. 1 OS/2 Warp 4 Readme 2 OS/2 Warp 4 Reference and Commands 3 OS/2 Warp 4 Tasks 4 "Performance Tuning OS/2 Warp," Ron Cadima, ISV Development Assistance, IBM Boca Raton, FL, 1995. 5 "OS/2 2.1 Performance Tuning for End Users," IBM, May 1993. 6 "OS/2 Warp Performance Pentium Pro P6 Performance Benchmark Guide," Duc Vianney, IBM TR54.915. 7 "OS/2 Client Tuning Worksheet," Tony White, IBM, Personal Systems Competency Center, May 1996. Trademarks The following terms are trademarks or registered trademark of the IBM Corporation in the United States or other countries OS/2, OS/2 Warp, OS/2 Warp Connect, OS/2 Warp Server, OS/2 LAN Server, DB/2, LAN Server 4.0, Bonus Pak, Personal Communications/3270 , Visual Age and Visual Builder, ThinkPad, NetFinity, OpenDOC, WebExplorer, SOM/DSOM, DIVE, System Performance Monitor/2 (SPM/2) The following terms are trademarks of other companies: TRADEMARK OWNER DOOM id Software Intel Intel Corporation Master of Orion MicroProse Myst Cyan, Inc. NetWare Novell, Inc. Pro AudioSpectrum Media Vision, Inc. QuickTime Apple Computer, Inc. Sound Blaster Creative Labs, Inc. THE 7th GUEST Virgin Interactive Entertainment, Inc. TIE Fighter Lucasfilm, Ltd. Western Digital Western Digital Corporation Windows, Win32s Microsoft Corporation Windows NT Server, Windows 95 Windows for Workgroups TME, TME 10 Tivoli Systems, Inc., an IBM Company OpenGL Silicon Graphics Amipro, L 1-2-3 Lotus Corp. BRender Argonaut Technologies Ltd. BYTEmark Byte Magazine. ColorWorks SPG Inc. Describe Describe Corp. MicroStation Bentley Systems, Inc. Pentium and Pentium Pro Intel Corp. SAS SAS Institute Inc., Cary, NC, USA. LANtastic Artisoft JAVA Sun Microsystems HyperACCESS Hilgraeve FaxWorks Keller Group Inc. CompuServe Information Manager CompuServe Pegasus Resource Monitor for OS/2 OnDEMAND Software, Inc. OS/2 Resource Monitor C.O.I. Consulting, Ltd. CPU Monitor BonAmi Software Corp. Performance 2.1 Clear and Simple, Inc. All other marks are the property of their respective companies. Notices References in this publication to IBM products, programs, or services do not imply that IBM intends to make these available in all countries in which IBM operates. Any reference to an IBM product, program or service is not intended to state or imply that only IBM's product, program, or service may be used. Any functionally equivalent product, program, or service that does not infringe any of IBM's intellectual property rights or other legally protectable rights may be used instead of the IBM product, program, or service. Evaluation and verification of operation in conjunction with other products, programs, or services, except those expressly designeated by IBM, are the user's responsibility. IBM may have patents or pending patent applications covering subject matter in this document. The furnishing of this document does not give you any license to these patents. You can send license inquiries, in writing, to the IBM Director of Licensing, IBM Corporation, 500 Columbus Avenue, Thornwood NY 10594, U.S.A. The following paragraph does not apply to the United Kingdom or any other country where such provisions are inconsistent with local law: INTERNATIONAL BUSINESS MACHINES CORPORATION PROVIDES THIS DOCUMENT "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Some states do not allow disclaimers of express or implied warranties in certain transactions; therefore, this statement may not apply to you. This publication could include technical inaccuracies or typographical errors. Changes are periodically made to the information herein; these changes will be incorporated in new editions of the publication. IBM may make improvements and/or changes in the product(s) and/or the program(s) described in this paper at any time. It is possible that this publication may contain reference to, or information about, IBM products (machines and programs), progamming, or services that are not announced in your country. Such references or information must not be construed to mean that IBM intends to announce such IBM products, prograaming, or services in your country. Requests for technical information about IBM products should be made to your IBM authorized reseller or IBM marketing representative. (C) Copyright International Business Machines Corporation 1996. All rights reserved. Note to U.S. Government Users. Documentation and programs related to restricted rights - Use, duplication or disclosure is subject to restrictions set forth in GSA ADP Schedule Contract with IBM Corporation. Table of Contents 1 Introduction 1.0 Why OS/2 Warp 4? 7 1.1 OS/2 Warp 4 features and functions 7 1.2 Performance differences from previous OS/2 versions 9 1.3 Software prerequisites 10 1.4 The software configuration menu 10 2 Capacity Planning 2.0 Capacity planning 12 2.1 OS/2 Warp 4 resource requirements 12 2.2 Main reasons for causing system performance bottlenecks in OS/2 Warp 4 13 2.3. Hardware issues 13 2.3.1 CPU 13 2.3.2 Memory 16 2.3.3. Disk drive 17 2.3.4 Video subsystem 20 2.3.5 COM port 20 2.4 Software issues 21 2.4.1 Planning for growth 21 3 Performance Monitoring and Tuning 3.0 Response time 22 3.1 Performance monitoring 22 3.2 Benchmarking 22 3.3 OS/2 Warp 4 performance tools 23 3.3.1 CHKDSK 23 3.3.2 Hard Disk Drive Monitor 23 3.3.3. PROFILER 24 3.3.4 PSTAT 25 3.3.5 SYSLEVEL 25 3.3.6 RMVIEW 26 3.3.7 TRACE 26 3.4 OS/2 external monitoring tools 3.4.1 System Performance Monitor/2 (SPM/2) 27 3.4.2 Simple CT 27 3.4.3 CPU Monitor 28 3.4.4 OS/2 Resource Monitor 28 3.5 Performance tuning 28 3.5.1 Problem definition 28 3.5.2 Identifying bottlenecks 28 3.6 Tuning Methodology 29 3.6.1 Define the problems 29 3.6.2 Hypothesize solutions 29 3.6.3 Design tests 30 3.6.4 Set values and run tests 30 3.6.5 Analyze the results 30 4 Basic OS/2 Tuning Procedures 4.0 Introduction 31 4.1 General system changes 31 4.1.1 The OS/2 Warp Center 31 4.1.2 The OS/2 Warp Guide 31 4.1.3 Animation 32 4.1.4 Changing display drivers 32 4.1.5 Minimize applications and folders 32 4.1.6 Starting applications 33 4.1.7 Use startup folder 33 4.1.8 Multitasking considerations 33 4.1.9 Schemes and color palette 33 4.1.10 Sounds 33 4.1.11 Font palette 33 4.1.12 System logo 34 4.1.13 Mouse 34 4.1.14 Desktop utilization 5 Advanced OS/2 Tuning 5.0 Introduction 35 5.1 Tuning tips for the Workplace Shell 35 5.1.1 The PMSHELL environment 35 5.2 Task scheduling 35 5.3 The CONFIG.SYS file 36 5.4 Single input queue 49 5.5 The AUTOEXEC.BAT file 49 6 Improving Application Performance 6.0 Application software 51 6.1 Tuning tips for OS/2 applications 51 6.1.1 SOMobjects 52 6.1.2 VisualAge C++ performance 52 6.2 Tuning tips for Windows applications 53 6.2.1 Win-OS/2 environment 53 6.2.2 Windows groups and Windows programs folders 53 6.2.3 Win-OS/2 virtual DOS sessions - common Vs. separate 53 6.2.4 Win-OS/2 standard and enhanced compatibility modes 53 6.2.5 Settings for Windows applications 54 6.2.6 Win32s support 55 6.2.7 Win-OS/2 setup 55 6.2.8 Win-OS/2 specific settings 56 6.2.9 General Win-OS/2 tips 57 6.2.10 Tuning tips for games 58 6.3 Tuning tips for DOS applications 60 6.3.1 DOS environment 60 6.3.2 Full screen vs. windowed 60 6.3.3 Multitasking DOS sessions 60 6.3.4 Tuning the DOS settings 61 6.3.5 Video settings 68 6.3.6 Mouse and touch sensitive settings 71 6.3.7 Settings affecting communications applications 72 7 Performance Exploitation of the Underlying Hardware 7.0 Introduction 75 7.1 Video display resolutions 75 7.2 Tuning tips for printing performance 76 7.2.1 Printer object settings 76 7.2.2 Fonts impact print speed 77 7.2.3 PRINTMONBUFSIZE 78 7.2.4 OS/2 spooled printing 78 7.2.5 Printing from DOS 79 7.2.6 Printing from WIN-OS/2 79 7.2.7 Printing from OS/2 applications 80 7.3 Tuning tips for speech performance 81 7.3.1 Hardware requirements 81 8 Tuning Tips for a Networked OS/2 Workstation 8.0 Introduction 82 8.1 Multi-protocol transport service 82 8.1.1 SOCKS support 83 8.2 OS/2 LAN Server/Requester 83 8.3 OS/2 Netware Requester 84 8.4 TCP/IP client tuning 85 8.5 DB2 client tuning -- SQL database performance 85 8.6 Lotus Notes client tuning 86 Appendix 1 - CONFIG.SYS File Insights 87 Cha pter 1 Introduction 1.0 Why OS/2 Warp 4? IBM's goal is to provide a more responsive OS/2 that is simpler and more intuitive to use, and provides easy connectivity. To achieve that end, OS/2 Warp 4 addresses three major issues: Ease of use - changes to the Workplace Shell interface Voice Navigation and Dictation Ease of connecting to whatever networked environment you wish 1.1 OS/2 Warp 4 features and functions OS/2 Warp 4 contains the following new features and functions: Voice Navigation and Dictation - Combining speaker independence and continuous speech, OS/2 Warp voice-enabled the operating system to navigate OS/2 and macros can be created to simplify repetitive tasks. Internet-Aware Desktop - New desktop objects for HTML, URL, Java class and FTP servers. These objects enable drag-and-drop from the Internet to the desktop and vice versa. The FTP object provides a folder view of a FTP directory. 256-color Exploitation - Visuals use more colors to give the user a 3D experience using texture, shadowing and curved edges. More System Fonts - A new condensed font style is added that uses less desktop real estate while improving legibility. File and Print Services Client - Converge LAN Requester and Peer for OS/2 to provide a single administration workstation. Users can share peer resources and administer peer and LAN resources. Objects on the desktop will inherit peer functionality in their context menus. The File and Print Client can connect to IBM-compatible networks such as: OS/2 Warp Server OS/2 LAN Server Windows NT Server PC LAN Program OS/2 Warp Connect Windows NT Workstation Windows 95 Windows for Workgroups LANtastic for OS/2 LANtastic for DOS PCOM Lite - Personal Communications/3270 (PC/3270) and Personal Communications/5250 (PC/5250)-- TCP/IP Entry Level 4.1 are replacements for TN3270, TN5250 and PMANT. The new emulators feature 32-bit code, full font set and automatic font sizing, custom color palette, improved cut and paste, APL support, command line (IND$FILE) file transfer, context sensitive help, popup keyboard, hot spots, PCMCIA and support problem determination aids. Users are limited to two sessions. Support for JAVA(tm) Applications - Full support for the Java language, Java runtime and Java applets. TrueType Engine - New support for TrueType, a ready source of inexpensive fonts. OpenDoc(tm) - Runtime support for cross-platform compound documents. Open32 Support - Support for subset of a Win32 APIs and messages to ease the porting of Windows applications. OpenGL - A high quality, portable 3D graphics API that will primarily enable technical and engineering applications (CAD/CAM) to be ported to OS/2 Warp. DPMI 1.0 Subset - Enablement for support of Win32s 1.25a compatibility and support of Borland 4 tools. Plug-and-Play (PnP) Support - Automatic detection and resource allocation for enabled devices as well as legacy ISA devices. An application is provided to view resource assignments. The framework has been established for more sophisticated operations in future releases. OS/2 Warp's PnP support does not include dynamic installation and configuration. Warm Plug/Warm Docking - Support for docking/undocking and the swapping of diskette drive and CDROM drive in specific models of IBM ThinkPad 755 series. Infra-red (IR) Support - ThinkPad-specific support for IR supporting the IrDA interface. Graphics Device Driver Model (GRADD) - New device driver model that reduces the IHV development effort and improves time-to-market. Device Driver Pak (DDPak) - A collection of OS/2 device drivers available from IBM and third-parties offered as-is for customer convenience. Display Data Channel (DDC) Support - DDC2 support for automatic enabled-display recognition and refresh rate setting. Realtime Musical Instrument Digital Interface (MIDI) - Framework and API for delivering high quality, realtime relative MIDI applications. Security Enabling Services (SES) - Enablement for operating system security services. System Dump Formatter - Utility to read and format system dump information. First Failure Support Technology (FFST) Probes - Capture all data relevant to the error at the time it occurs. DMI Interface - Support for the Desktop Management Interface, an industry standard way to manage Pcs. TME NetFinity - Software to allow administrators to view, monitor and initiate actions to ensure the smooth operation of PCs. Software Registration (ART) - Online registration tool to encourage customers to register the software electronically via a modem or the Internet, FAX, mail or even the telephone. Users are gently reminded periodically until registration is completed. Retrieve Software Updates - Automatic software retrieval and install of fixes and upgrades via the Internet. XPG4/ULS Support - Provide ability for easier application adaptation of international requirements such as native languages, local customs and coded character sets. Bonus Pak Changes - Collection of personal productivity applications including word processor, spreadsheet, charting, report writer, database, calendar, monthly planner, appointment book and phone book. IBM Works 3.0 contains fixes, memory management improvements, updated help, HTML support, updated word processor and graphics filters and a button bar for commonly used features. Remote Support for OS/2 - Allows IBM service representative to dial into your system to assist with problem determination and resolution. HyperACCESS Lite - Async communications program to access bulletin board services. The update includes maintenance and other refinements such as user-defined modem strings and more colorful icons. CompuServe Information Manager - Provides access to the CompuServe online service. CIM 2.03 includes fixes and removes the OS/2 registration requirement. HP JetAdmin and MarkVision for OS/2 delivers an advanced network printing solution that enables you to easily install, configure, query, and troubleshoot network-attached printers from your OS/2 Desktop. FaxWorks - Allows FAXes to be sent and received. Includes features of a basic answering machine. Supports drag-and-drop. FAX/data integration through a new interface for data applications to pass answered call to FaxWorks. AskPSP - AskPSP consists of an expert system with a natural language interface. It can be used to resolve customer problems on OS/2 Warp. This tool is also used by IBM Service and Support. The technical database, updated monthly, is available by subscription to the OS/2 Technical Connection CDROM. The following features and functions have been updated in OS/2 Warp 4: Integrated install - Updated for OS/2 Warp, the install program gives the user an easy and an advanced path. The user can also selectively install, re-install or uninstall components. Controls and Visuals Visuals - Use more colors to give the user a 3D experience using texture, shadowing, and curved edges. Dialogs - File Open and Close dialogs provide tree views of directories and allow for filetype selection. Horizontal Style Notebook - Notebook settings add a horizontal tab option. This new style allows information to be presented more concisely without taking up much space. Close Button - Close applications with a single click. Folder Menu Bars - Menu bar access for common operations within folders. Users can also utilize the context menu (Mouse Button 2) for these same operations. User Interface Redesign Background Bitmaps - Bitmaps with texture and color schemes. Exploit use of more colors for higher degree of texture and depth. Arrange Options - Desktop and folder icon alignment according to user preferences. Pointers - Greater selection of pointers for user customization. Font Palette - System-defined or user-defined selection of fonts for text Color Palette - System-defined or user-defined selection of colors for visual controls. Scheme Palette - System-defined or user-defined selection of fonts and colors. Sound Schemes - System-defined or user-defined selection of sounds for system events. System Tutorials Update - Designed to help users get up-to-speed, with a focus on getting connected. Also includes a section on speech. Help System Updates - Enhancements to give the help author more control over content, presentation, and navigation. Migration Database - Database of optimal settings for popular OS/2, DOS and Windows applications. The database is used during install to migrate previously installed applications. Includes additional Windows and new Win32s applications. Async Read-Ahead - File system studies disk read patterns, anticipates a disk read and makes it available in memory to improve system throughout. Network Transports - NDIS device driver support for a variety of LAN adapters. Netware Client 2.11+ for OS/2 - This is the same level of code that was shipped in OS/2 Warp Connect 3.0 and OS/2 Warp Server 4 with fixes. TCP/IP DHCP/DDNS Client - Dynamic Host Configuration Protocol eases network administration by dynamically allocating and reusing IP addresses. Dynamic Domain Name Service simplifies network access, operation and change with dynamic resolution of IP addresses to IP hosts. Socks Security - Permits TCP/IP applications to access the Internet through many standard firewalls. FTP and TFTP Client and Server - File transfer to and from a remote host. Telnet Client and Server - Logon to and from a remote host. Client is now based on PC/3270. REXEC and RSH Client and Server - Execute command on and from a remote host. SNMP Agent and Manager - Communicate and obtain status information and manage network resources. WebExplorer - WebExplorer 1.1a supports HTML 3.0 and contains numerous fixes and updates. Remote Access Client - The Remote Access Client provides LAN access via dial connections (asynchronous, synchronous, ISDN or X.25). The Remote Access Client can dial into either a LAN Distance Connection Server or OS/2 Warp Server. In addition, a Remote Access Client can dial directly to another Remote Access Client to establish a virtual network. Mobile Office Services - Mobile Office Services transparently caches files while connected to an IBM-compatible or NetWare network and allows the user to continue using these files even when disconnected. When the network connection has been re-established, Mobile Office Services detects the differences between the cache and the files on the network and prompts the user for resolution. Win32s 1.25a Support - Win32s 1.25a application support. SOM/DSOM - Provides a language independent, cross platform architecture for sharing objects. Device Driver Update - Updates of many device drivers shipped in previous versions of OS/2. PCMCIA Enhancements - The latest level of code that supports IBM PCC and other OEMs. This consists of card and sockets services, cardbus and multi-function card support, an enhanced user interface as well as updates to warm docking. Advanced Power Management 1.1- Update to support suspend, resume and device management and control. Enhanced IDE Support - Enhanced to support the SMART standard for hardware failure alert and DMA capabilities for PCI IDE hard drives. Printer Support - New printer device drivers included. Multimedia Support - Direct Audio Routines (DART) used by speech navigation and dictation. DIVE Enhancements - Enhancements for hardware video accelerators, video capture, MPEG playback and full-screen support for applications needing high frame rates. 1.2 Performance differences from previous OS/2 versions Some of the changes that gave OS/2 Warp 3 better performance than previous OS/2 versions are as follows. A new link parameter, /EXEPACK, which was used on many system files when OS/2 Warp was compiled, compresses resource and message files by 20 to 30%. These files load 2 to 3% faster, on average. Some page frames are "zero compressed" (similar to PKZIP) and put in areas of memory that is already allocated but that has extra space. This allows a page frame to be swapped from RAM to RAM (which happens in nanoseconds) versus swapping from RAM to the hard disk (which takes milliseconds). Up to 250 of these pages can be moved to different areas of RAM instead of the SWAPPER.DAT file. Many system DLLs (dynamic link libraries) are now being swapped out to the hard disk. This makes it much quicker to recall them. A lot of overhead is required to load a shared DLL from the file system versus saving it and its associated system data in the SWAPPER.DAT file. The SWAPPER.DAT file, when initialized, is put in the largest contiguous space of the FAT file system. Previously the system was not concerned with swapper fragmentation. The internal file system in the SWAPPER.DAT file now has a 4 KB cluster size instead of 2 KB. This change makes swapping a 4 KB page more efficient. Some system DLLs have been merged, so less overhead is needed to load them into memory and notify all tasks of their locations. For example, PMMERGE.DLL contains three old system DLLs: PMGRE.DLL, PMSHAPI.DLL, and PMWIN.DLL. Although these DLLs are still in OS/2 Warp, their function is simply to forward their calls to PMMERGE.DLL. Some other DLLs that are merged are DOSCALL1.DLL and MMPM.DLL. A method of addressing called basing puts some system DLLs at an absolute address to reduce the overhead of finding them in memory. OS/2 Warp 4 contains all of the aforementioned changes as well as enhancements to the FAT file system (FAT deserialized and optimized asynch read ahead), CD-ROM asynch read ahead, page tuning many system DLLs, single input queue, as well as changes to the memory caching default size and system loader fixup scheme. Furthermore, there are changes made to improve TCP/IP throughput and faster response time for network administration commands. 1.3 Software prerequisites OS/2 Warp 4 can be installed over the following systems. OS/2 1.3 OS/2 2.0 and 2.1 OS/2 for Windows OS/2 for Windows plus Service Pak DOS 3.1 or greater with Windows 3.1, 3.11 DOS 3.1 or greater with Windows for Workgroups 3.10 or 3.11 OS/2 Warp V3.0 OS/2 Warp with WIN-OS/2 V3.0 OS/2 Warp Connect V3.0 OS/2 Warp Connect with WIN-OS/2 V3.0 over itself in a totally empty partition TIP: OS/2 Warp 4 shipped at the equivalent of OS/2 Warp 3 with Fixpak 20 level. 1.4 The software configuration menu Many OS/2 parameters can be modified during or after installation. This section overviews those paramters that can be modified during the installation process. Each of these tunable parameters will be discussed in greater detail later in this document. From the OS/2 Setup and Installation panel, there will be three menus: Options, Software Configuration, and Help. NOTE: From the Options menu bar choice, you can: Install the selected features Format other drives Access an OS/2 command From the Software Configuration menu bar, you can specify the location for the swap file. You can also change the OS/2 and DOS configuration settings of your system. The OS/2 parameters that you can change are: Printer monitor buffer size Buffers Disk cache Maxwait Swap Minfree Threads Memman Protect Memman Swap Priority The DOS parameters that you can change are: Break Open FCBS Protected FCBS RMSize Chapter 2 Capacity Planning 2.0 Capacity planning The OS/2 operating systems, in particular OS/2 Warp 4, have evolved to take advantage of new technologies and strategies, such as client/server, voice navigation and dictation, internet aware desktop, JAVA support, etc. The resulting changes in the software infrastructure and system platforms require careful system planning to ensure OS/2 Warp 4 performs as a cost-effective information technology platform. Personal computers have limited resources to handle increasingly complex operating systems and applications. Resources such as CPU, disk, and memory must perform well together and deliver adequate response times to satisfy a user's requirements. Hence, capacity planning becomes an important issue when determining the impact of OS/2 Warp 4 on your system. To ensure the correct level of resource to meet and support your computing needs, you need to: 1.Assess the current performance levels of your system. 2.Identify any additional computing needs you will have in the near future. 3.Determine the performance impact these needs will have on the existing configuration. 4.If the performance impact is not acceptable, tune the current configuration for optimal performance and perform step 3 again. 5.If performance is still unacceptable, a more detailed performance analysis becomes necessary to determine where the performance bottleneck is occurring. Additional hardware may be required. By employing validated performance analysis and tuning methodologies and systems tools, you can accurately measure the utilization of your computer resources. This will the smooth integration of OS/2 Warp 4 into your existing environment. 2.1 OS/2 Warp 4 resource requirements Your system performance depends largely on how OS/2 Warp 4 and the underlying hardware work together. The 32-bit OS/2 Warp 4 operating system exploits the Intel 32-bit X-86 architecture through the flat memory model, native protected mode and virtual 8086 mode though paging and multiple virtual DOS machine sessions. The flat memory model allows for a very large (4 GB) single address space referred to as flat memory. Call/return times are reduced by eliminating the need to switch segments manifested in a typical 16-bit application. While all previous 16-bit APIs are still completely supported, the remaining OS/2 Warp 4 APIs are now 32-bit, thus improving performance and enhancing function. In addition, OS/2 also provides support for advanced disk hardware, Direct Memory Access for its parallel port, and many industry standard audio and video devices. Like previous versions of OS/2, OS/2 Warp 4 supports all existing 16-bit and 32-bit OS/2 applications, most DOS applications including those that use EMS, XMS or DMPI memory in the full screen or windowed virtual DOS machine session. Windows application support is also included in OS/2 Warp by providing both Windows 3.1 and Win32s environments for running Windows applications seamlessly on the OS/2 workplace shell, in concurrence with DOS and OS/2 applications. Several of OS/2 Warp 4's new features and enhanced functions require a powerful processor, more physical memory, and a larger hard drive. If you experience sluggish response time after installing OS/2 Warp 4 you can use some of the performance tools shipped with OS/2 Warp 4 to determine the cause of the problem and apply the following guidelines to obtain the best performance out of OS/2 Warp. Without Voice Navigation and Dictation: Intel 486 DX 33MHz or higher processor 12MB to 16MB of RAM Installation by selecting options requires 100MB-300MB disk space Easy Installation (OS/2 Warp preselected options) requires 200MB disk space 640x480 resolution display with 256 colors recommended (SVGA monitor) IBM compatible mouse is required OS/2 compatible CDROM drive and 1.44MB 3.5" diskette drive "A" 14.4K or higher modem or network connection for Internet access OS/2 supported sound card for multimedia With Voice Navigation and Dictation, OS/2 Warp 4 requires For speech navigation, Intel Pentium 75MHz or higher with 4MB additional memory For speech navigation and dictation, Intel Pentium 100MHz or higher with 8MB-12MB additional memory Installation by selecting options requires 100MB-300MB disk space Easy Installation (OS/2 Warp preselected options) requires 200MB disk space 640x480 resolution display with 256 colors IBM compatible mouse is required diskette drive A and CDROM driver 14.4K or higher modem or network connection for Internet access Sound card for multimedia or speech High quality microphone for speech (requires Active Noise Cancellation feature, ANC, for optimal performance.) 2.2 Main reasons for causing system performance bottlenecks in OS/2 Warp 4 There are three areas where performance can be constrained: memory, disk, and processor. Memory constraints occur when you attempt to run more programs in memory than there is actual memory. The hardware allows OS/2 to execute beyond the real memory by allowing paging or swapping, i.e., to allow code and data to be moved from memory to disk. As memory becomes scarce, system performance degrades as access time to code or data written to disk now includes the disk access time required to read back into memory information that was moved out. It probably also required moving off to disk some information to make room for the returning information. This activity can cause extremely poor performance. Disk constraints occur when your application requires large number of disk accesses quickly. Since the hard disk must complete one I/O request before starting the next request, multiple requests can start to queue, causing poor performance. Between I/O requests, the hard disk must move the head from one location to the next. Thus a hard drive with slow seek time will become a major bottleneck if the support for high I/O rate is required. The processor constraints occur when processor-bound instructions and multiple concurrent tasks require heavy processor time. Since OS/2 is a true multitasking system, the likelihood of becoming CPU constrained is increased as the number of concurrent task execution increases. In the following sections, we will examine the functions of major system components and how each would contribute to the overall system performance. 2.3 Hardware issues 2.3.1 CPU The CPU plays a vital role in system performance. It is responsible for processing the millions of instructions necessary to produce work. The speed of the microprocessor (and also the amount of installed memory) typically has the largest effect on the performance of the computer system. The microprocessors system clock rate, measured in millions of clock steps per second, or Megahertz (MHz) dictates the speed at which the system runs. The faster the clock rate, the faster the performance. Most CPU's in today computer systems are at least 80486 chips. The 80386SX, SL and SLC, as well as the 486SLCx have an external data path of 16 bits while 80386DX and 486DX and above processors have an external data path of 32 bits. This distinction becomes significant as the shift towards 32-bit software begins to proliferate the market. 32-bit instructions, processing on a 16-bit CPU must become two 16-bit instructions in order to be processed. The processor with a 16-bit external data path can result in about 10% lower performance than an identical processor of the same speed with a 32-bit data path. The following charts illustrate the various processor chips, their respective speeds and their cache option. Comp arison of 386 Processors Feature 386SX 386SL 386SLC 386DX Speeds available (MHz) 16 20 20 25 16 20 16 20 25 33 Internal Processor Cache N/A N/A 8K N/A Internal Processing (bits) 32 32 32 32 External Data Path (bits) 16 16 16 32 Comparison of 486 Processors Feature 486SLC 486SLC2 486SLC3 486SX 486SX2 486SL 486DX 486DX2 486DX4 Speeds available (MHz) Numbers represent both internal and external processor speeds. 25 40/20 50/25 60/20 66/33 75/25 100/33 20 25 33 50/25 25 33 25 33 50 50/25 66/33 75/25 100/33 100/50 Internal Processor Cache 16K 8K 8K 8K 8K 16K Internal Processing (bits) 32 32 32 32 32 32 External Data Path (bits) 16 32 32 32 32 32 Note: The 486SLC2 processor runs internally at twice the speed of the rest of the system, such as 40/20MHz producing performance faster than a 25MHz 486DX, but less than a 50MHz 486DX. It is up to 271% better than a 20MHz 386SX, up to 99% faster than a 20MHz 386SLC, up to 53% faster than a 20MHz 486DX and up to 20% faster than a 25MHz 486DX. The 50/25MHz 486SLC2 is faster than an Intel 33MHz 486DX. The 75/25MHz 486SLC3 processor is up to 40% faster than the 50/25MHz 486SLC2, 187% faster than a 20MHz 386SLC and up to 424% faster than a 33MHz 386SX. The 486SLC is identical to the 486SLC2 in all respects, except clock doubling. It is approximately equivalent in performance to a 486DX, but adds power management features the 486DX lacks. The 486DX2 processor runs internally at twice the speed of the rest of the system, such as 50/25MHz or 66/33MHz, producing performance faster than a 33MHz 486DX, but less than a 50MHz 486DX. The 486DX4 processor runs internally at three times the speed of the rest of the system, such as 75/25MHz or 100/33MHz, producing performance in excess of a 486DX2. Compa rison of Pentium Processors Feature Pentium P5 Desktop Pentium P54C Desktop Pentium P54LM Notebook Speeds Available (MHz) Numbers represent both internal and external processor speeds. 60 66 75 90 100 120 133 150 166 200 75 90 100 120 133 150 Clock Multipliers (e.g., 2X = 133/66MHz) 1X 1.5X, 2X, 2.5X, 3X 1.5X, 2X Internal Processor Cache 16K 16K 16K Internal Processing (bits) 32 32 32 External Data Path (bits) 64 64 64 The Pentium Pro processor (also known as the P6 processor) is the latest generation processor family from Intel. The Pentium Pro processor includes significant architectural innovations and enhancements, like Dynamic Execution, multiple branch prediction capabilities, 256K L2 cache in the package, etc. The result is a significant boost in system performance -- especially with 32-bit software. Since OS/2 and especially OS/2 Warp 4 is a 32-bit operating system, the Pentium Pro processor delivers optimal performance with 32-bit OS/2 applications. Summary of performance data for P6-150 and P5-133 A summary of the performance data between P6 and P5 is given below. The experiment was done on a P6 processor running at 150 MHz, 256 KB Level 2 cache, 32MB of physical memory, 1.28 GB IDE hard drive, Matrox PCI display adapter card. All measurements were done with the display resolution set at 1024x768x256 except where it is noted. The P5 system is from Micron Technologies. It has a P5 processor running at 133 MHz, 256 KB Level 2 cache, 32 MB of physical memory, 1 GB SCSI hard drive, and Matrox PCI display adapter card. Again, all measurements were done at 1024x768x256 resolution except where it is noted. OS/2 Warp Connect was used on both systems with no special options or setup. OS/2 Warp was installed with multimedia support using the default installation options. The FAT file system was used in the study with default dynamic disk cache size. There are five types of benchmarks used in the study: 1.Trade magazines benchmarks such as BYTEmark from BYTE Magazine 2.Industry Standard benchmarks such as the OPENGL CDRS and DX from the Graphics Performance Council 3.32-bit OS/2 applications benchmarks such as VisualAge from IBM, SAS from SAS Institute Inc., MicroStation from Bentley Systems, and ColorWorks from SPG Inc. 4.Multimedia benchmarks such as software MPEG playback, direct video APIs interface DIVE and 3-D driver interface BRender from Argonaut Technologies Inc., and finally 5.The mix 32- and 16-bit OS/2 business applications such as Describe, Amipro, Lotus 1-2-3 and IBM C++ used in OS/2 program development. In general, the average ratio of performance improvement for P6 over P5 is 1.63. In particular, the ColorWorks and DIVE benchmarks seem to gain the most, more than 2X improvement, while others tend to gain somewhere around 50%. The BRender 3-D library from Argonaut Tech which is built upon DIVE seems to take the full advantage of the P6 floating-point performance. Its ratio of performance is around 1.88, almost twice of that P5. It is also observed that applications that are computational intensive such as 3-D graphics rendering in the MicroStation benchmark gain about 1.5X on the P6 platform. The industry standard graphics test from GPC using the CDRS and DX viewsets also scores well on the P6, around 1.5 times over P5. The legacy OS/2 applications benchmark which is a mix of 32- and 16-bit code ran only 30% faster on the P6. The chart below illustrates the average measurements and the performance ratio between the two systems. Processor: P6-150 P5-133 P6/P5 Manufacturer: Intel Micron Ratio Memory Configuration: 32MB 32MB Display Resolution: 1024x768x256 Improvement Display Adapter: Matrox Matrox for P6 Applications Metrics BYTEmark 2.0 iterations/sec 1.49 OPENGL - CDRS frames/sec 2.23 1.51 1.47 OPENGL - DX frames/sec 0.89 0.58 1.53 VISUAL AGE - Visual Builder seconds 80.4 104.4 1.3 MOVIE PLAYER - Bundy seconds 13.78 20.01 1.45 SAS seconds 16.4 27.84 1.7 Argonaut - Robot frames/sec 64 34 1.88 ColorWorks seconds 14.06 31.02 2.21 MicroStation seconds 31.55 46.94 1.49 Legacy Apps (Describe, Amipro, L123, IBM C++) seconds 61.5 80.5 1.31 DIVE frames/sec 273 128 2.13 Average 1.63 Geometric Mean 1.61 NOTES: 1. ColorWorks was run at display resolution 1024x768x16M System bus The bus is the internal pathway along which signals are sent from one part of the computer to another. Personal computers typically have one of three bus architectures: Industry Standard Architecture (ISA) bus, often referred to as "AT bus". This bus is the 16-bit bus initially developed for IBM's AT (Advanced Technology) computers. The bus includes 8-bit slots for downward compatibility with earlier adapters, but includes 16-bit slots for improved, AT-compatible adapters such as 16-bit VGA adapters. It supports data rates of 8MB/sec. Micro Channel Architecture (MCA) bus. A proprietary 32-bit bus used in IBM PS/2 computers. This bus operates at 10MHz with burst data rates of up to 80MB/sec. Enhanced Industry Standard Architecture (EISA) bus. A 32-bit bus that, unlike the MCA bus, is backward compatible with ISA adapters. Peripheral Component Interconnect (PCI) bus. A 32-bit bus standard used in most new computers. This bus provides the greatest performance of all the above, operating at 33MHz with burst data rates of up to 132MB/sec. The system bus plays an important role in balancing system performance. If you have a high speed CPU and video adapter on an ISA bus system, this system is not well balanced. The CPU is a great deal faster than the system bus. For example, if your processor is a 486DX 33MHz CPU and you have an ISA bus VGA video adapter (remember, ISA is 16-bit), the system has the capability to transfer data at speeds greater than 33MB/second but the ISA bus can only transfer data at 8.33MB/second. While this isn't a very practical example, it illustrates the potential for an imbalanced system caused by a system bus that is slower than the processor, particularly when running I/O intensive applications such as databases. 2.3.2 Memory Memory, often referred to as random-access memory (RAM), is the computer's primary storage space used to execute instructions. Memory is generally available on the system board and/or on adapter cards. The speed of the memory is expressed in nanoseconds, with the lower the value the better. Memory speed is important in that faster memory provides faster access to the information stored there. Memory location is also important. Memory on the system board (motherboard) can generally be accessed by the processor faster than memory located on an adapter card. The adapter card memory requires access through the system bus, slowing down the time from processor to memory. Having adequate memory in a system will also reduce the disk access because paging or swapping is decreased. If the operating system does not have to handle paging I/O requests, system performance will improve. If the swap file is large, and changing from one application to another results in I/O requests, the system would benefit from additional memory or performance tuning. A cache is a small group of very high speed memory chips and the support circuitry that manages them. Some microprocessors have a built-in cache while others have it residing outside the microprocessor on the system board. Others have extended the cache built into the microprocessor with a second-level cache designed to feed information into the microprocessors internal cache more efficiently. This is called a "level 2" cache. The memory cache increases the overall performance of the computer system by automatically gathering commonly needed information, such as program instructions and data, and then very quickly providing it to the microprocessor the next time the data is requested. Since the memory cache can respond much more quickly than the system's memory, the system's performance is improved every time the information contained in the cache is used. A small internal cache is faster than a larger external cache, due to the delay in accessing an external cache. OS/2 Warp 4 memory working set The working set for OS/2 Warp 4 is defined as the set of memory (pages) referenced in the last n time of certain measurement intervals. The working set includes both resident and locked pages. The following data represent the working set of different OS/2 Warp systems running under different environments, connected (with TCP/IP and NetBIOS installed) and not connected (base operating system only). The test was performed on a 486/33 system with 16MB of memory, 1.6GB IDE hard drive, FAT file system, and Tseng SVGA ET4000 display adapter. OS/2 Warp 3 3,996KB OS/2 Warp 3 Connected 6,212KB OS/2 Warp 4 4,996KB OS/2 Warp 4 Connected 6,860KB It is important to note that the number of unique pages accessed during a sliding window of 12 snapshots (1 minute) taken on the same system but with 40MB of memory (unconstrainted memory scenario) is as follows. OS/2 Warp 3 12.68MB OS/2 Warp 3 Connected 19.97MB OS/2 Warp 4 Connected 25.27MB 2.3.3 Disk drive Fixed disk performance is important to the overall performance of a computer. The performance of a fixed disk refers to the rate at which information can be located and transferred between the fixed disk and the memory. The disks average seek time, average latency and data transfer rate determine how the disk subsystem will contribute to or hinder overall system performance. These disk performance statistics are generally available from the disk manufacturer. Data on a fixed disk is stored in concentric rings, or tracks, on the disk surface. To read from a fixed disk, the actuator must first move the read/write head to the proper track. The average time it takes for the actuator to move the read/write head over the proper track is called the average seek time - usually expressed in milliseconds. Once the read/write head is located over the right track, it must wait until the disk rotation brings the right part of the track under the read/write head. The average time it takes for this to happen is the average latency2 of the drive - also expressed in milliseconds. Finally, after the proper track and proper part of the track are positioned under the read/write head, the information is transferred between the disk and the disk controller circuitry, one bit at a time in a continuous stream as the disk surface passes underneath the read/write head. The speed at which this is done is called the data transfer rate and is expressed in millions of bytes per second (MB/second). It is important to consider the disk drives performance statistics when purchasing a computer system. These statistics play an key role in the overall performance of the system. The shorter the seek time and latency the better. The higher the data transfer rate the better. All of these factors determine how the disk subsystem will contribute to or hinder overall system performance. OS/2 Warp 4 provides significant new function compared to OS/2 Warp Connect. Depending on the selections you make during installation, this version will require a maximum of 350 megabytes of hard disk space. The following table indicates how much disk space is consumed by each selectable component. It will be very useful in planning your installation. NOTE: If you have a very large partition (> 1 GB) formatted for FAT, the install will require 550 MB due to the large cluster size required by the FAT file system. Failure to provide sufficient hard disk space will result in installation failures and will require re-installation. ===> DO NOT ATTEMPT INSTALLATION WITH BARELY ENOUGH SPACE. During the installation process, you will be asked to select which of the following install options: Advanced Install or Easy Install. If you selected the Advanced installation option then you would see the OS/2 Setup and Installation screen which enables you to configure the software. The list of software that you can select in OS/2 Warp 4 is as follows. Disk Space Default Assistance Center 10.03 MB OS/2 Tutorial 4039 KB OS/2 Command Reference 825 KB Yes REXX Information 768 KB Yes OS/2 Warp Guide User Interface Agent 4,367 KB Yes Fonts 2.42 MB Yes Courier 273 KB Yes Helvetica 629 KB Yes System Mono-Spaced 86 KB Yes Times Roman 596 KB Yes Courier (outline) 320 KB Yes Times New Roman (outline) 259 KB Yes Optional System Utilities 2.29 MB Yes Backup Hard Disk 27 KB Yes Change File Attributes 36 KB Yes Display Directory Tree 33 KB Yes Manage Partitions 233 KB Yes Label Diskettes 33 KB Yes Link Object Modules 450 KB NO Picture Viewer 122 KB Yes PMREXX 146 KB Yes Recover Files 45 KB Yes Restore Backed-up Files 35 KB Yes Sort Filter 31 KB Yes Installation Utilities 419 KB NO Create Utility Diskettes 192 KB Yes Service/Diagnostic Aids 542 KB Yes Optional System Components 2.30 MB Yes OpenDoc 5,842 KB NO Voice Type 23,753 KB NO Security 496 KB NO Bonus Pak 36.42 MB NO CompuServe 2,736 KB NO HyperAccess Lite 656 KB NO IBM Works 14,411 KB NO Fax Works 1,266 KB NO VideoIn 467 KB NO AskPSP 4,008 KB NO Remote Support Tool 1,441 KB NO Printer Utilities JetAdmin 560 KB NO JetAdmin Port Driver 1,645 KB NO MarkVision 4,879 KB NO MarkNet Port Driver 5,238 KB NO Tools and Games 24.19 MB Enhanced Editor 1,933 KB Yes Search and Scan Control 68 KB Yes OpenGL 1.0 3D Library 4,905 KB NO Optional Bitmaps 10,073KB NO Solitaire-Klondike 2,762 KB Yes Pulse 43 KB Yes Chess 2,828 KB Yes Mahjongg Solitaire 2,151 KB Yes OS/2 DOS Support 1.54 MB DOS Protected Mode Interface 29 KB N/A Virtual Expanded Memory Management 19 KB Virtual Extended Memory Support 9 KB N/A WIN-OS/2 Support 6.11 MB Readme Files 136 KB Yes Accessories 1,039 KB Yes Screen Savers 73 KB Yes Sound 115 KB Yes Multimedia Support 22.41 MB Base Multimedia Support 19,294 KB Yes Multimedia OpenDoc Support 2,929 KB NO Software Motion Video 728 KB Yes High Performance File System 470 KB Yes Network Services File and Print Client 13 MB TCP/IP Services 28 MB Remote Access Client 4 MB System Management Client 7 MB Netware Client 6 MB Mobile Office Services 3 MB TIP: Selecting All Features During Advanced Install - A Full install requires approximately 275 megabytes for code and data, 25 megabytes for SWAPPER.DAT, and 50 megabytes for any additional programs and applications. Deselecting Features During Advanced Install - A single 350 megabyte partition is the least complex environment. You can deselect some features or install some features to partitions other than the OS/2 boot partition. The following features allow partition selection during install: Speech BonusPak Connect Java Multi-Media Windows Emulation Using Easy Install - Easy install selects a subset of OS/2 features for installation on the C: partition. This selection is based on the hardware configuration. For example, Multi-Media is installed if a sound device is detected. Some features that are not installed during Easy Install are: Opendoc Java Toolkit and Samples BonusPak Security Some optional BITMAPS Some documentation for Command Reference and REXX The selection panel for Connect allows installation of features consistent with the connection hardware and software. Easy install requires between 150 and 200 megabytes depending on your selections and hardware configuration. 2.3.4 Video subsystem Computers can provide video support on the system board or on an adapter. Video support is identified by the mode and resolutions that they can support. The greater the resolution and number of colors, the better the picture. Unfortunately, better resolution and more colors usually translate into slower system performance. VGA (Video Graphics Array) was introduced in 1987 and soon became a popular video standard. VGA systems are capable of displaying 16 colors at a resolution of 640x480. SVGA (Super VGA) refers to a group of high-resolution analog video adapters. SVGA provides higher resolutions and more colors than VGA adapters. Most SVGA adapters with 1MB of video memory are capable of displaying 256 colors in a resolution of 1024x768. XGA (Extended Graphics Array) was introduced by IBM in 1990. It is an accelerated analog video adapter which uses a coprocessor to provide hardware-assisted drawing functions. XGA-2 is a newer version of XGA which includes performance improvements, higher refresh rates, non-interlaced mode and support for resolutions of 1360x1024 with 16 colors. Many new video adapters are coming available that can't be classified as VGA, SVGA or XGA. They are using new and more powerful chipsets that show improved performance over SVGA by using on- board processors for some graphics functions. These chipsets are called accelerators. They include previously discussed XGA chipsets, as well as new accelerated SVGA chipsets such as S3, Weitek P9100, Mach 8/32 and Tseng W32i. Two main features on your graphics card affect video performance the first, the card's onboard memory, and the other the card's accelerator chip and bandwidth. There are three common types of onboard memory found on graphics cards, Dynamic RAM (DRAM), Window RAM (WRAM), and Video RAM (VRAM). DRAM is cheap, but its single-ported design requires a system clock cycle to reset the chips before each refresh of screen data. VRAM is dual- ported, able to deliver data and reset in a single clock cycle for inherently faster performance. It's also more expensive than DRAM. WRAM is a form of VRAM that does faster fills and accellerates video playback and animation. WRAM is not only dual-ported, but also requires fewer transistors than VRAM, hence lowering costs while providing a few graphics-specific speed-ups such as support for aligned bit-block transfers (BitBlts). The type of graphics memory you choose is almost as important as the amount. DRAM is the least expensive, but its single-ported design makes it relatively slow; dual-ported VRAM is more costly, but much quicker for true-color work. A variety of other single-ported (such as EDO DRAM and SDRAM) and dual-ported (such as WRAM) variations fall between the two on the price/performance scale. The graphics accelerator cards architecture, or more specifically, it's bandwidth also plays a crucial role in graphics subsystem performance. Bandwidth is defined as the amount of information that can move along the cards data path. The bandwidth between the graphics card's accelerator chip and its display memory can be as wide and quick as graphics card manufacturers care to make it. Over the last several years, 32-bit graphics accelerators have yielded largely to 64-bit accelerators, with 128 bit cards becoming more and more common. To keep refresh rates high, team a fast 64-bit or 128-bit accelerator with dual-ported display memory to handle the volume of data that true-color and multimedia applications demand. 2.3.5 COM Port Machines with a buffered UART (Universal Asynchronous Receiver/Transmitter), for example the 16550A will have better communications performance than machines without buffering, for example the 16450. The performance of DOS communications programs is particularly impacted by using systems with these buffered communications chips on their COM ports. The MODE command can be used to determine whether your system has this buffered UART. A buffered UART at level 16550A or equivalent is nearly essential for high speed communications. Use the command: MODE COMx, where x is the communications port number. If you see "BUFFER=N/A" then you do not have a buffered UART for that port. 2.4 Software issues 2.4.1 Planning for growth File systems OS/2 Warp supports two file systems for use on your hard disks: FAT and HPFS (High Performance File System). The HPFS file system supports file and directory structures different from the FAT file system. The OS/2 Warp HPFS file system is much better than the old FAT system used in DOS, although FAT is retained for backwards compatibility reasons and is used for diskettes. HPFS is faster, allows long file-names, is less likely to lose data and uses disk-space more efficiently than does FAT. Another advantage of HPFS over FAT is in the area of Extended Attributes (EAs). EAs are data attached to a file and used to provide information about the file they are attached to. For example, the name of an object that appears in an OS/2 folder or on the OS/2 Desktop is stored in EAs. In HPFS, EAs are part of the HPFS file control block which is read when the file is opened. In FAT, EAs are stored in a separate file in separate clusters and require additional I/O to access them, and are therefore slower. HPFS has two limitations. Native DOS applications can't see HPFS formatted disks (although DOS programs running in OS/2 Warp can and there exists a driver to read HPFS disks from plain DOS), and the HPFS driver takes approximately 264KB of memory. TIP: Install only the file system needed by the operating system accessing your data. If you plan to boot a DOS or Windows system natively (via the dual boot option), then any data that will be accessed must exist on a FAT disk partition. However, If you will only be running DOS and Windows applications in an OS/2 Warp VDM (Virtual DOS Machine), then the file system can be either HPFS or FAT. Also, when accessing a file on a server, and the server file system is HPFS, you do not need to install HPFS on your local client machine. HPFS only needs to be installed on a computer when a partition on a local hard disk is formatted as HPFS. FAT is best suited for disk partitions that are 80 MB or less in size or that have a limited number of files installed. Usually, 256 files is a good target, with up to 500 acceptable. The number of files become important because FAT files are allocated based on a cluster size. The cluster size is determined by the size of the disk partition and can be 2K, 4K, 8K or higher. Since most file sizes are not an exact multiple of the cluster size, disk space is not optimally used. For example, installing DOS, Windows and OS/2 Warp on a 100MB partition resulted in 2.2 MB of disk space that could not be used. A 100MB partition will use a 2K cluster size. If you were to use a 540MB partition size, then your cluster size would be increased to 16K and a significantly greater amount of disk space will be lost. HPFS files are allocated based on a 512 byte granularity instead of a cluster size, therefore fragmentation is greatly reduced. Also HPFS is especially efficient when handling large partition sizes, > 100 MB, and large numbers of files, > 500. One thing you should look out for is to not allocate more than 5000 files in a sub-directory or directory. Allocating more than 5000 files can lead to degraded performance. The HPFS file system shipped with the OS/2 Warp product has a cache limit of 2 MB. It is recommended that HPFS be installed on systems with 16MB of memory or more and large disk partitions. If HPFS is not being used, you should remark the HPFS driver from the CONFIG.SYS file. This driver uses 264KB of RAM. If the HPFS statement configures a HPFS cache, the maximum amount of RAM consumed by the cache and the driver could be at much as 2312KB (264KB for the file system driver + 2048KB for the max cache size = 2312KB). Even if there is no HPFS partition on your system, it will cost between 200 and 250K in working set memory, as well as the space for the HPFS cache. If you are installing OS/2 Warp on an existing DOS and or Windows system, you should not install HPFS. When your system is up and running, you can check the working set of your system. If there is enough free memory and you wish to create a HPFS partition, then you can use selective install to install the HPFS support. Remember that any data stored in the HPFS partition can not be accessed if you boot your machine under DOS. Use HPFS if your application uses many small files or a very large data file like in database applications. Both FAT and HPFS file systems have disk caching, lazy writing and read-ahead. File system parameters can be changed after installation. The default values set by the installation procedure are good for average users. It is recommended that when you set up your hard disk, you create a minimum of 3 partitions. One will be for the operating system(s), one for your applications and static data files, and another for dynamic data files and temporary files. Decide whether you want to use Boot Manager or Dual Boot. If you select Dual Boot, then OS/2 must be installed with the FAT file system. Chap ter 3 Performance Monitoring and Tuning 3.0 Response time Response time is the key indicator used in measuring and tuning a system. It can be defined as the time interval from when a user initiates a process until that process has completed. For example, response time can be measured as the interval of time from when a user presses the enter key to initiate a database query until the data is displayed on the screen. The productivity of a OS/2 Warp 4 user is largely dependent on adequate system response time. The user should be able to interact freely with the application without having to wait for the system to respond. Response time requirements may vary among users and even among applications. A three to fifteen second response time may be adequate for a complex inquiry application that is only run occasionally, but a sub-second response time may be required for more frequently used applications such as word processors or spreadsheets. This section introduces the concept of performance monitoring, measurement, and tuning. It also covers performance tools shipped with OS/2 Warp 4 as well as tools available from external sources. 3.1 Performance monitoring Monitoring the performance of critical system resources is invaluable in identifying the cause of performance problems. Performance monitoring is the first step to take in solving performance-related issues. There are numerous performance monitoring tools that measure response time, disk activity and other variables that impact the performance of the system. These tools will assist in understanding possible causes and subsequent resolution of the problem. Once the problem has been identified, the process for alleviating it can begin. This process, or tuning methodology, needs to be well thought out and documented through to resolution. 3.2 Benchmarking A benchmark is a test that measures the performance of a system or subsystem on a well-defined task or set of tasks. Test scenarios, or benchmarks, are designed to achieve consistent repeatable results during the tuning process. Benchmarks are necessary for creating an effective, systematic approach to performance tuning your system. The benchmark should represent a work environment very similar to the one being tuned. Benchmarking is essential for measuring progress while tuning a system. Characteristics of a good benchmark include: Each test is repeatable. Each iteration of a test is started in the same system state. There are no functions or applications active in the system outside the ones being measured unless the scenario includes some amount of other activity going on in the system. Do not even have them started and sitting idle, since this will use up RAM resources and increase the likelihood of swapping. Benchmarks can also be used as monitoring and diagnostic tools. By running a benchmark and comparing the results against a known configuration, you can potentially pinpoint the cause of poor performance. Similarly, a developer can run a benchmark after making a change that might impact performance to determine the extent of the impact. 3.3 OS/2 Warp 4 performance tools The OS/2 WarpCenter provides a CPU monitor utility that shows the system activity and a disk space monitor program that shows the amount of disk space available in all partitions. In addition, there are many other operating system utilities that you can use to check your system integrity if you perceive a performance degradation has occurred. They are as follows. CHKDSK - disk integrity checking HDMON - hard disk monitoring PROFILER - file repairing PSTAT - process monitoring RMVIEW - resource allocation monitoring SYSLEVEL - operating system and corrective service level analyzing TRACE - events tracing 3.3.1 CHKDSK CHKDSK can detect lost clusters on your disk. These are parts of files that the system did not save completely and that take up space on your disk. If CHKDSK finds these, it prompts you with a message asking if you want to convert lost chains to files. If you type a Y (yes), CHKDSK converts these parts into files that you can examine and delete to save space on your disk. If you type an N (no), CHKDSK deletes these parts of files from your disk. The files CHKDSK creates from lost chains follow this naming convention: FILEnnnn.CHK (nnnn is a sequential number starting with 0000). TIP: To start chkdsk, type the following command in any OS/2 window. CHKDSK /x where x = F or V or C or F:n The /C and /F:n parameters shown at the end of the CHKDSK command syntax are only used with the High Performance File System. Type this command at a DOS command prompt to produce a memory storage report. CHKDSK gives accurate information only when a hard disk is not in use. CHKDSK does not work in DOS sessions on drives that have an ASSIGN, JOIN, or SUBST command in effect. Also, CHKDSK does not work on network drives. You should run CHKDSK occasionally on each disk to check for errors. If errors are found, CHKDSK displays the error messages and produces a status report. If you enter a file name after CHKDSK, the OS/2 operating system displays a status report that gives the number of noncontiguous areas occupied by the file. CHKDSK also produces a storage report. To search for and recover lost file clusters on the drive that is the hard disk from which you normally start the OS/2 operating system, follow these steps: 1.Insert the system installation diskette in diskette drive A. 2.Restart the system. When the Logo panel appears, remove the installation diskette and insert diskette 1. Press Enter to continue. 3.Insert diskette 2 when requested. 4.At the first text panel that appears (Welcome to OS/2), press Esc. 5.If the drive to be searched is a drive formatted for HPFS, the file UHPFS.DLL has to exist on the same diskette as CHKDSK, or UHPFS.DLL has to exist in a directory in the LIBPATH statement. To display the LIBPATH statement, enter TYPE \CONFIG.SYS in the drive of the disk that the system started from. 6.In order for the system to display error messages, the file OSO001.MSG has to be on the same disk as CHKDSK or it has to exist in a directory in your DPATH statement. To display your DPATH statement, enter DPATH at the command line. 7.Run CHKDSK from drive A, specifying drive C as the drive to be c.

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