FOREWORD:
This is a jargon-less white paper I made in defense of UNIX over the wintel juggernaut (Yes! I know you don't get many references for this over the net as well. Any mention of Informix below while talking about the UNIX/RISC/RDBMS combination can be extrapolated to include Oracle, Sybase and Ingres as well. Informix here has been just taken as an example.
In response to various inputs from the marketplace, companies striking it out with UNIX under RISC have at various times actively considered the pros and cons of porting their higher end customized application software products on PC platform. The important criteria here was to find out whether these companies could then offer a cost effective solution considering hardware investments to their smaller prospective clients. This evaluation has been done on the backdrop of clients using their software in a mission critical environment. The various factors taken into consideration were reliability, security, technology, scalability, maintainability, user-friendliness and of course, proveness of the system.
Ambiguities exist in the definition of PC based solution. The definitions are made based on the type of hardware and operating system as well as RDBMS in certain cases. Thus solutions with Intel Pentium, Windows NT and MS SQL Server all get classified as PC based solutions. We are taking each of these instances giving reasons for their lack of provenness in the higher end mission critical applications.
PCs have been generally considered to have advantages of ease of use and lower cost. But, considering the total picture presents a different view. The user friendliness of the UNIX system for the operations staff is basically the GUIs and screens of the software application and this has no bearing with the server being RISC/UNIX based or Intel/NT based. The cost advantages vanish when the overall cost is considered. Thus the cost benefits in Total Cost of Acquision (TCA) does not involve savings in networking, hardware other than the processor and application software.
The savings comes from the processor, some of the peripherals and the RDBMS if MS SQL Server is used instead of the proposed Informix RDBMS. An Intel/NT combination thus has a cost advantage on about 25% of the entire system and within this, the actual difference can come to about 5-10%.
These savings are neutralized once the Total Cost of Ownership (TCO) is considered. The cost of maintaining several PCs distributed across the length and breadth of a port is many times that of a UNIX-system with terminals as front ends.
Application software for huge operations in sectors like transportation, mining and so on involve what is called as Mission-Critical Applications. Thus, provenness of the platform becomes a critical parameter. Adding to the TCO are the problems associated with performance issues of an Intel/NT/SQL Server combination.
UNIX has been there in the marketplace for over two decades and is a mature technology which can seamlessly incorporate newer demands of technology. NT still suffers drawbacks on security issues, both in terms of levels of access as well as in probability of virus attacks. Reliability of the UNIX system comes from its capacity to run without performance degradation under varying loads depending on port traffic. Also, scalability in terms of newer technologies of clustering, parallel databases etc. are not available on NT today.
The PC has become an excellent, powerful, user friendly tool for an individual user for office automation and other low-end applications. But when it comes to mission critical applications, with underlying concerns of security, reliability, performance and scalability, the PC still remains very much in the unproven area.
RISC, UNIX & Informix OR Pentium, Win NT & SQL Server?
We are addressing the comparative advantages of going for a PC-based solution against a RISC-processor based solution on the following lines
· Total cost of ownership
· System environment benefits
The Scope - What is a PC based solution?
The discussion here is scoped at comparing
· processors (Intel Pentium versus RISC
processors)
· operating systems (Windows NT vs. UNIX)
and
· RDBMSs (Microsoft SQL Server vs. Oracle
/ Informix / Ingres)
PC based solution can be any of the following combinations:
# UNIX/Pentium based solution
# NT/Pentium based solution
# NT/RISC based solution
# UNIX/Pentium based solution
UNIX/Pentium solution
UNIX operating system has been ported in 486/Pentium environment. The UNIX offerings available are SVR4, SCO UNIX, PC Solaris & UNIXWARE. But these have not proved to be very popular due to various factors. The number of applications developed and made available under these platforms have been very few. Also, this implementation suffers from insufficient high availability features like parallel server and clustering.
NT/Pentium based solution
NT is the most popular enterprise Operating System running under Pentium. NT is extremely well suited for Desktop, Workgroup, Office Automation and other departmental applications. Within this combination, SQL Server and Oracle are the popular RDBMS packages.
This combination also suffers from performance issues under higher loads and raises questions on security. Currently, Compaq and HP are coming out with clustering software and other high availability features, but these remain largely unproven.
MS SQL server works under this combination and offers significant cost advantages compared to Oracle. But SQL Server still lags in features compared to other major RDBMS players like Oracle, Informix and Ingres. "SQL Server 7.0, with features such as a full implementation of row-level locking, multisite replication and a Windows 95 version will not ship until second half of 1998" says a Gartner Group study. (Microsoft SQL Server: Delays, Partners and Product Tiers by A Hilwa dated 27 June 1997).
NT/RISC Solution
Activity has begun to port NT operating system under a RISC hardware environment, DEC’s Alpha being the best instance. But apart from helping current NT users get access to more powerful RISC based servers, this do not offer much of an advantage. Price/Performance ratios remain the same as that of DEC Alpha machines running under UNIX. But due to the nature of the hardware (RISC), some clustering features have been made available.
The proposed solution works under a UNIX/RISC
system with Informix as the RDBMS. The salient points of this solution
in comparison with the other three combinations discussed above are given
in the following sections.
Total Cost of Acquisition (TCA)
The total cost of the system can be broadly divided into two,
(a) the initial cost or the Total Cost of
Acquisition (TCA)
(b) the recurring cost or the Total Cost
of Ownership (TCO)
Total Cost of Acquisition (TCA)
The TCA of any Information System broadly comprises of four components:
1. Hardware
2. System Software
3. Networking
4. Application Software
A PC-based solution basically means change in item-1 and partly in item-2.
The application software continues to be the container terminal management system with the required constituents and features.
The networking decision also remains unchanged, i.e., whether to go for FDDI or 10-base T Ethernet, optic fiber or twisted pair and so on. Since technology and extent of cabling remain the same, there would be no changes in the cost factor here.
The two main constituents of system software are the Operating System and the RDBMS. There will also be other minor components like server manageability software as well. A RISC processor (e.g.: HP PA-RISC or SUN SPARC) based system typically works with UNIX and an RDBMS like Oracle, Informix or Ingres. This UNIX - Oracle/Informix/Ingres configuration works with PCs as well. But the OS and RDBMS can change for a PC based configuration (Windows NT with MS SQL Server).
So the actual change occurs in the hardware part of the total system. This is typically constitutes 25-30% of the total cost. So regardless of PCs or RISC systems, 70-75% cost remains the same.
Total Cost of Ownership (TCO)
The TCO on the other hand includes the TCA and over and above it, the day to day expenses of maintaining the total system. These cover the broadly (i) equipment cost of upgrades (ii) manpower cost of maintenance
As the system requirements grow, upgrades as well as enhancements are made in hardware, network, system software and application software.
Application software upgrades typically include additional features, functionalities and even modules. For instance, Radio Data Terminal technology can be typically integrated at a later stage when batch mode operations become too unviable for an on-line, real time application.
System software upgrades involve buying additional user licenses as the number of operations staff using the application software increase.
Hardware upgrades depend directly on the scalability of the system, i.e., the ability of the system to support additions or upgrades in processor, memory, hard disk, peripheral controller cards etc. These remain more or less the same, but Intel-based systems suffer from scalability drawbacks.
Adding to this is the manpower cost. The cost of maintaining PCs spread over the entire organization is many times greater than that of supporting a UNIX-based server running VT-100 (or equivalent) terminals. This has resulted in the evolution of the concept of a Network Computer which is still in its infancy.
Against this, for a UNIX-system, administration costs are concentrated at the server side. One skilled person will be required for maintaining the server, but this proves to be much lesser than having several people of lesser skills (and hence, lesser salaries) being required to manage and maintain the distributed PCs across the various departments and locations.
System Environment Benefits
Most of the high-end, mission-critical application software currently operate under a RISC based hardware with UNIX as OS. These can be of any of the various options like HP/UX, SUN Solaris, DEC UNIX etc.
Hardware system performance is specified for a given application software on the basis of standard performance ratings (Transactions Per Minute or TPM). So regardless of whether the microprocessor is CISC (for PCs) or RISC, the specified TPM rating has to be adhered to.
The other components of the hardware are designed based on the transactions in the system, the data base size & load, the number of users and so on. These are main memory, hard disk drive, hard disk controller cards, network interface cards and so on. These also will remain the same for PCs or RISC machines.
The hardware cost difference thus comes in the microprocessor alone.
A PC-based hardware system can operate under UNIX or Windows NT for a high transaction environment. The choice of RDBMS for Win NT is typically MS SQL Server.
While Win NT offers advantages in terms of simpler usage and messaging, these have severely restricted the functionality. It is limited to NT domains which don’t tie into non-NT networking. With a very low level character based interface, UNIX makes it easy to access all administrative functions remotely. It can be implemented in turnkey systems using simple GUI interfaces.
Scalability issues are still present in NT as it is still not mature. Consequently, NT still requires administrators to reboot the OS following minor configuration modifications. Other weaknesses include 2 GB limit on addressable memory, limited administration tools and lack of comprehensive directory and security systems.
Compared to NT, UNIX has much stronger capabilities of handing large scale application. UNIX solutions effectively deliver upgrade paths, which run from workstations to workgroup server to multiprocessor enterprise server to parallel supercomputers.
UNIX encompasses a variety of vendors and an array of technologies, but as a group or generally, they adhere to a reasonable standard operating environment, and applications are often available to multiple UNIX platforms.
When the OS is used to handle complicated transaction, there is a major difference in processing time. There is an exponential increase in processing time and consequential performance degradation as number of users increase.
Though an emerging RDBMS, MS SQL Server is still
unproven in large transaction applications as in ports. With just 5% market
share, SQL Server is still in its infancy and has not stabilized regarding
a lot of features which come as standard with other popular RDBMSs.
CONCLUSION
Taking into account the factors of
· Scalability of hardware & OS
· Performance under varying loads
· Provenness in multiple environments
· Higher-end features like clustering,
parallel database etc.,
it could be noticed that the cost benefit in going for the Pentium-Win NT- SQL Server is minimal and purely short term.
AFTERWORD:
This note was posted at this site in April, 1998.
Several changes are taking place at breathtaking pace in the IT industry.
There might be temptation to crtique the above write-up as well. Do mail
in your feedback to me. It will be most appreciated.
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