I don't want to start another "discussion" on this topic, I just thought that this was a good article. It appears that Unix is still king for VLDB or mission critical apps... Frank ---------------------------------------------------------------------------- ----- DPRO-89898 Mary Hubley, Mary Ann Richardson Gartner Group Technology Overview 24 January 2001 Server Operating Systems-Unix Versus Windows 2000: Perspective Summary Has Unix finally met its match in Windows 2000 Datacenter Server? Despite its gains in the midrange and departmental market, Windows-based platforms have never been able to supplant Unix when it came to building systems for enterprise applications such as large data warehouses, large-scale science and engineering simulations, online transaction processing (OLTP), and the myriad Web e-commerce and B-to- B applications that demand 24x7 availability. The Datacenter Edition of Windows 2000 aims to change all that. Note Microsoft announced the availability of Windows 2000 Datacenter in September 2000. Table of Contents Technology Basics Technology Analysis Business Use Standards Technology Leaders Insight List Of Tables Table 1: Microsoft Windows 2000 Datacenter Server Enterprise Features Server Operating Systems-Unix Versus Windows 2000: Perspective Technology Basics Will Windows 2000 Datacenter Server finally propel the Wintel platform into the enterprise? While Unix is here to stay, users who have been waiting for Windows to have the capability to run their enterprise computing environments can start to find it in the Datacenter Server Edition of Windows 2000. Datacenter has been designed to do away with many of the drawbacks of its predecessor, Windows NT, that made the Wintel platform unsuitable for 24x7 environments. For example, Microsoft estimates that over 40 percent of Windows NT applications errors are due to incompatible third-party device drivers. To avoid these and other such errors, users will not be able to purchase Datacenter and install it on their own hardware. Datacenter will only be available through hardware vendors that have tested their products under Microsoft's Windows Datacenter Program (WDP) and have been certified to license and support Datacenter Server. Microsoft has created the Windows Hardware Quality Labs (HQL) so that hardware and software vendors can ensure that their products work with Datacenter and other versions of Windows 2000. Hardware products that pass the corresponding Hardware Compatibility Test (HCT) are placed on the Datacenter Hardware Compatibility List (HCL), which lists the hardware that is guaranteed to work with Datacenter. And, of course, hardware that isn't on the HCL can't be sold in a Datacenter system. Any hardware vendor that sells Datacenter on its systems must ensure that all hardware drivers, kernel level software, virus software, disk and tape management software, backup software, etc., are certified for Datacenter. These vendors will also be required to maintain their Datacenter-compatible systems for the life of the current version of Datacenter plus 18 months. Datacenter vendors will provide all maintenance services for their systems including full installation of the OS and all drivers, an evaluation of Datacenter in the customer's environment, and on-site service with company employees or subcontracted through a third party. To ensure reliability for large-scale enterprise applications, Datacenter systems must guarantee a minimum uptime of 99.9 percent; higher uptimes will be required with clustered systems. In addition to how it will be sold, Datacenter includes a number of competitive features and enhancements for the enterprise-level market. Table 1: Microsoft Windows 2000 Datacenter Server Enterprise Features Horizontal vs. Vertical Scalability Previously, Windows platform users could only scale horizontally. With horizontal scalability, capacity is increased by adding more servers through the use of Windows Network Load Balancing (NLB) and Server Clustering. But while horizontal scaling avoids a situation that entails a single point of failure, having so many boxes to deal with makes it harder to manage and control. This is especially true for large-scale OLTP environments. Vertical scalability makes it much easier. Vertical scalability lets users scale up by adding more hardware resources, such as RAM, hard drives, and microprocessors, to a single system- thus, users have the increased power but only one system to manage. Before Windows Datacenter, users had but one choice- Unix- if they wanted their systems to scale vertically. Unix went beyond the 4GB of RAM and 8-multipprocessor support limitations of Windows. Now that Datacenter supports up to 32 processors and 64GB of RAM in a single system, vertical scalability has become a viable option within a Windows environment. However, this is still well below the 64-processor support available from high-end Unix machines, so users will still need horizontal scaling as systems expand. Windows 2000 Memory Management Enhancements Memory management determines how well the operating system will support multiple applications executing simultaneously. Both Unix and Windows 2000 provide extended facilities for ensuring that individual applications do not affect the operation of the OS. Both operating systems support protected kernels and protected memory areas for individual applications. Thus, if an application fails due to a memory access failure, only the allotted area will be affected- not the entire OS. Limitations on RAM have been overcome in Windows 2000 through the Windows 2000 Enterprise Memory Architecture (EMA). EMA is designed to let applications access large amounts of RAM efficiently. In Windows 2000 Advanced Server, two EMA technologies are employed: a 4GB Tuning (4GT) feature and Physical Address Extension (PAE), which allows Windows AS to access up to 8GB of RAM. In Datacenter that limit is raised to 64GB. This significantly reduces disk paging since both the OS and applications can exist entirely in RAM. In Windows 2000 Advanced Server, 1GB of the RAM normally reserved for the OS can be set aside for applications, giving them access to up to 3GB of RAM. To access the full 8GB in AS, applications will need to program to the AWE Application Programming Interface (API) and ensure that AS is running with the PAE-enabled kernel. The AWE API provides applications with a way to access RAM above 4GB. Use of the AWE API will provide applications with up to 7GB of space on AS. Datacenter works the same way but the amount of RAM that can be accessed is, of course, larger. Directory Structure Limitations to Windows NT Directory Services made it unsuitable for enterprise environments. Windows 2000 has replaced the Windows NT directory with Active Directory (AD). AD provides a single point of administration for servers, services such as DHCP and DNS, users, printers, and other network resources. Active Directory uses Internet Domain Name Service (DNS) as the partitioning scheme. By using standard Internet domain names to identify objects within the directory, the Active Directory service can provide a directory to internal, external, and public services- all within the same database. When querying or updating the directory, the Active Directory system supports the Internet standard Lightweight Directory Access Protocol (LDAP). However, Active Directory does not use the LDAP system for storing information in the database and is therefore not subject to the same limitations that apply to the referral system offered by traditional LDAP implementations. The Active Directory system supports the authentication of users across the entire network. Windows 2000 uses a single directory for the entire network; multiple domains are supported within the single directory. The domains become logical, rather than physical boundaries between machines. Each user is provided with access to the resources within each domain and, therefore, only needs to log in to the network once. There is no need to connect to multiple individual domains. All servers within a Windows 2000 network are peers of each other, and synchronization of the authorization is automatic in both directions across the entire server network. Thus, all servers within the network are aware of the authority available to each user, while also being capable of modifying that authorization information and having it replicated across the network. Active Directory is also used and made available to other applications including the Web services supported by IIS, Microsoft Exchange, and Microsoft SQL Server. The same authentication information is shared by all applications and also controls access to the files and folders on each server. There is no need for a separate authorization scheme under Windows 2000. Unix employs a standard set of directories that can contain only standard sets of files. However, Unix lacks a standard directory service, but NIS, NIS+, and DCE directory services can be integrated into Unix. For example, Solaris 8 provides a centralized authentication facility through the traditional Network Information Service (NIS/NIS+). The NIS/NIS+ system uses a central server that propagates information to other servers within the network at specific intervals. Authorization to a local machine is, therefore, controlled from a central server, although for speed, clients cache the information. The main disadvantage to the client of this system is that it does not provide a single point of authorization; the user must authorize the connection to each server, even if they all use the NIS/NIS+ system. Sun has implemented iPlanet directory server and directory-service extensions to address the need for a centralized directory-services solution on Solaris 8. Remote Management Unix has been perceived to be easier to manage in distributed systems because of its built-in remote management capabilities. Most Windows NT administrative programs have to be run on the physical machine to be managed; there is no built-in ability to manage the machine remotely. Managing an NT server remotely required the addition of specialized GUI utilities from Microsoft or other third-party vendors. Windows 2000, on the other hand, has added remote administration facilities. These include the remote administration mode of Terminal Services, which provides users with a GUI-based method to remotely administer any Windows 2000 server over the network; and Windows 2000's Microsoft Management Console (MMC) management framework, which supports remote instrumentation based on WBEM and CIM standards. Winsock Direct Winsock (Windows sockets) is a programming interface that lets TCP/IP-based applications such as Internet Explorer run under Windows. Windows 2000 now includes Winsock Direct, which provides standard Winsock applications with the capabilities they need to work on high-speed System Area Networks (SAN). Without Winsock Direct, most SAN application programming required an understanding of proprietary transport technology, because most SANs do not use TCP/IP. Winsock Direct allows TCP/IP applications to run unmodified over SANs; thereby, increasing performance by stripping away the TCP/IP overhead that is not needed when applications are not communicating over the Internet. Resource Management For resource management, Datacenter Server includes a Process Control tool that can be used to allocate resources, such as processors and memory, to an application. Process Control is an MMC-based tool and command line utility that gives administrators the ability to finely control resources so that particular applications can be assigned specific system resources. It works with a Datacenter-specific kernel object called a Job object, which is used to collect one or more server processes into a single, named unit. Administrators can used the capabilities within Job objects to create rules in Process Control such as a rule that prevents an application from using too much RAM or processor time, or one that assigns scheduling priority to processes or process groups. Nevertheless, Windows 2000 does not yet support such advanced operating-system functions as Dynamic Reconfiguration or Alternate Pathing found on Solaris 8 that can protect systems from hardware failure. OS Integration Windows 2000 has enjoyed a slight advantage over Unix systems because of the OS's high degree of integration with key infrastructure components, such as Web servers, messaging systems, and Web application servers. While Unix requires that these components be purchased and installed separately, Windows 2000 integrates these features into the base operating system. Many users prefer getting all their software from a single source. However, choosing Windows 2000 also locks a user into the COM+ development environment. Since COM+ runs only on Windows 2000, the growth path for COM-based applications is inherently dependent upon Windows 2000's future capabilities. On the other hand, Unix platform development is compatible with a wide range of platforms ranging from the PC to IBM mainframe clusters. Technology Analysis Business Use Unix has become the de facto standard for building large-scale application servers such as Internet services, enterprise messaging systems, database management systems, and transaction processing systems. Unix has gained considerable popularity as an e-business server, and is being deployed for everything from a simple Web site to a full-blown e-commerce server encompassing Web-to-host connectivity. While Windows Datacenter is recommended for many of these same applications, thus far Win2K's stability under a range of demanding applications remains unproven. Meanwhile, due to the complexity of Active Directory, the majority of Windows 2000 implementations have been deployed as replacement systems in mixed environments of WindowsNT/2000 or Window/Unix where Active Directory is largely disabled. Active Directory has been deployed to great advantage within those sites implementing new applications where none existed before. Standards Most versions of Unix are Posix-compliant; Windows NT supports a subset of the POSIX.1 standard. Both systems support native TCP/IP. Microsoft supports Kerberos in AD but uses a data field in the Kerberos ticket that is not used by other systems. This can add significant management overhead when adding Windows 2000 servers to an existing Kerberos environment. Technology Leaders While there are several dozen versions of Unix in use today, those with the largest share of the commercial Unix market are Sun's Solaris, HP's HP-UX, and IBM's AIX. Of the three, Sun Microsystems' Solaris is the leading server and is found in some of the world's largest corporations. Solaris takes the lead for reliability, availability, and scalability- in large part due to its dynamic reconfiguration capabilities and (on the Enterprise 10000 server) strong resource management functions. Solaris also has highly competitive HA clustering options, software RAID, and SMP capabilities. AIX has traditionally led the others in system management. Its Java-based system management tool, which has a Windows 95-like look-and-feel, provides remote management capabilities via Java-enabled Web browsers. AIX also has the strongest set of Internet features. The leading vendor of Windows 2000 Datacenter Server is Unisys. The Unisys ES7000 is the only server that runs up to 32 Intel processors on Microsoft's Windows 2000 Datacenter Edition OS. Compaq, HP, and Dell are reselling modified versions of Windows Datacenter on the Unisys ES7000 under their own labels. Insight Unix's greatest competitive strength lies in its relatively superior reliability, availability, and scalability. However, in order to achieve these advantages users must implement expensive and proprietary hardware. High-end Unix capabilities are not offered on Intel hardware. For Intel platforms, the only enterprise server option is Windows 2000 Datacenter Server. -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Frank Pettinato INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). 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