Bridging the gap, NT is making strides in scalability, but it isn't anywhere close to catching up with Unix.
By Susan Breidenbach
nwfusion.com
Network World, 4/13/98
Microsoft Corp.'s Windows NT Server continues to evolve as an enterprise-level operating system, but it's still playing second fiddle to Unix. Despite the claims trumpeted last May at Microsoft's Scalability Day, NT isn't likely to fill all your network operating system needs until some time in the next century.
Enterprises are deploying NT at an ever-increasing rate, but in its traditional supporting role as a file and print and applications server. Unix is still the star of the strategic systems show, thanks to superior scalability, reliability and management talents.
"At the enterprise level, we don't see NT playing at all right now,'' says Mike Prince, chief information officer (CIO) for Burlington Coat Factory Warehouse Corp., in Burlington, N.J. "The stability and scalability of Unix really precludes our use of NT in that space. NT just isn't there yet.''
But Microsoft keeps working at the enterprise level relentlessly, unwilling to concede any part of the high-margin operating system business. De-spite some well-publicized implementation gaffes and security breaches, NT's metamorphosis into an enterprise platform proceeded steadily over the past year. And the much-ballyhooed release of NT 5.0 is full of enterprise-oriented functionality.
"The NT 5.0 beta has some enterprise features, like the new directory and large memory support, that are looking very good,'' says Sushil Vyas, vice president in charge of non-Unix servers for the Capital Markets Group of First Union Corp., in Charlotte, N.C. "If those things end up in the final release, they will bridge most of the gap between NT and Unix.''
Meanwhile, companies such as Burlington Coat Factory Warehouse are finding plenty of use for NT in lower tiers of the network hierarchy. In fact, usage studies indicate that the NT vs. Unix war barely exists outside the arena of marketing rhetoric. The platforms are still highly complementary today.
In a 1997 survey of users, International Data Corp. (IDC), of Framingham, Mass., found that file and print service was the primary reason companies were acquiring NT, followed by messaging and Internet access. Database hosting was a distant fourth. In contrast, database hosting was the primary reason users acquired Unix systems, followed by file and print, custom applications and Internet access.
Although NT is enjoying enormous sales growth, the increase is coming from market expansion and displacement of other network operating systems - not at the expense of Unix.
Going upscale
The biggest technology gap between NT and Unix is on the scalability front. In a recent survey conducted by Forrester Research, Inc., of Cambridge, Mass., 62% of IT managers at large organizations viewed NT as unscalable. Although NT theoretically supports up to 32 processors in a symmetric multiprocessing (SMP) system, NT couldn't scale beyond two at the beginning of last year.
"There weren't any eight-processor systems, and even scaling up to four was iffy,'' says Michael Hurwicz, an analyst with Patricia Seybold Group, Inc. in Boston. "Now scaling up to four processors is quite practical.''
Experts aren't impressed with NT's eight-processor performance, but Hurwicz points out that eight-processor boards aren't yet available from Intel Corp. To test NT, analysts assembled eight-processor NT machines by combining two four-processor boards - a less-than-optimal hardware foundation.
While NT's added scalability is a start, it still pales in comparison to what Unix can do. IBM's AIX can run across a massively parallel 512-node system, and each node can be an SMP computer. In a single box, SunSoft, Inc.'s Solaris scales up to 64 processors and provides better linear scalability than NT at even the four- and eight-processor levels.
At four processors, NT is scaling by a factor of about 1.6, so each additional processor is only adding about 60% of its stand-alone processing power to the four-processor mix. In contrast, Solaris scales by a factor of 1.8 to 1.9, or 80% to 90%, according to Tom Goguen, senior product manager for Solaris at SunSoft, in Menlo Park, Calif.
"This lets companies increase the power of a server as demands on that server grow,'' Goguen says. "It is a lot cheaper to add processors and disk capacity to a single server than to put new servers in.''
"NT is a major resource pig,'' agrees Thom Stark, president of Stark Realities, a network consultancy in El Cerrito, Calif. "You have to throw an incredible amount of hardware at NT to get it to behave acceptably. For example, whenever Microsoft says a piece of its software requires a certain amount of RAM, that means what it will take to run like a slug on drugs. Figure on adding at least twice as much.''
Heavy lifting
Despite these limitations, NT has made some impressive gains in scalability.
"In standard testing, we've gone from 2,100 transactions per minute and 1,800 concurrent users in October of 1995 to 16,000-plus transactions per minute and more than 14,000 concurrent users today,'' says Ed Muth, group product manager of NT enterprise products at Microsoft. That's nearly an eightfold increase in 30 months.
However, such benchmarks just show how some products perform relative to others; they don't say a lot about real-world capabilities. In heavy transaction processing environments, very few NT servers are handling 400 concurrent users, says Dan Kusnetzky, program director of operating systems research at IDC. In contrast, some high-end Unix systems are supporting 30,000 concurrent users.
And Unix is hardly standing still while Microsoft plays catch-up. IBM set new Internet world records with its AIX- and RS/6000-based Web site for the recent Winter Olympics in Nagano, Japan. The site handled 650 million hits during the 16-day event and reached a peak rate of 103,429 hits per minute.
"The performance gap between Unix and NT may actually be widening,'' says Miles Barel, software product marketing manager for IBM's AIX division in Austin, Texas. "There's almost no scalability limit on Unix.''
The lack of true enterprisewide directory services has been causing administrative and security problems for NT shops even at the file and print server level. NT currently limits domains to 40,000 directory objects, although a single NT 5.0 domain will be capable of holding up to 10 million objects. Administrators also will be able to configure multiple domains in a tree that conveys implicit trust among the branches.
In the meantime, managers can use third-party products such as Novell, Inc.'s Novell Directory Services for NT to scale NT domains across the enterprise.
NT's 32-bit architecture poses another weakness. The ability to address memory in 64-bit chunks means more data can be kept in memory and disk access is reduced. This very large memory (VLM) addressing boosts the performance of databases and data warehouses and enables them to scale much larger. The 64-bit architecture also increases I/O bandwidth so data can be transferred much faster.
"You want a 64-bit system for one of two reasons,'' says Morgan Gerhart, program director for META Group, Inc., of Burlin-game, Calif. "Most people want the VLM capability so they can load up huge buffers in their database.'' Consequently, Unix started evolving into a 64-bit operating system several years ago as developers added VLM extensions for database applications.
Other 64-bit components followed, and SunSoft is adding the final piece - 64-bit virtual addressing - to Solaris for SPARC this fall.
Following Unix's lead, Microsoft is beginning to address VLM capabilities to prepare for forthcoming 64-bit Merced processors. "When Merced ships, NT 5.0 will have 64-bit extensions that will enable big buffers, which is what 95% of the big applications need,'' Gerhart says.
Software generally lags hardware advances by several years, and industry observers scoff at Microsoft's promise to deliver a complete 64-bit version of NT when Intel's first Merced chipsets ship in 1999. However, this isn't what's preventing deployment of enterprise databases and data warehouses on NT. A full 64-bit operating system is actually more important on the workstation side for computer-intensive applications.
In any case, Intel and its traditional hardware OEMs appear to be hedging their bets. Instead of relying entirely on Microsoft's NT efforts, they are asking SunSoft to have a 64-bit version of Solaris ready for Merced when it ships. Intel has also promised to help The Santa Cruz Operation, Inc. release a 64-bit version of UnixWare 7.
Reliability realities
Where mission-critical enterprise applications are concerned, scalability issues become academic if a system can't be trusted to stay up all the time. Some Unix systems have been continually available for a few years, even throughout maintenance and upgrades. You can even change the IP address on a Solaris server without bringing it down, and SunSoft has promised live operating system upgrades in the near future.
In the NT environment, systems have to be rebooted whenever changes are made to the Windows Registry or when memory leaks threaten to precipitate a server crash."Wintel programs don't run for weeks on end without locking up,'' Burlington Coat Factory Warehouse's Prince says. "NT is getting better at this, but it's not like Unix environments where programs almost never crash.'' Wintel hardware also tends to be less reliable than Unix platforms.
Some of NT's shortcomings in the reliability arena are due to its heritage as a desktop operating system. The operating system design priorities for a desktop graphical user interface (GUI) and a multi-user server are very different.
Microsoft's one-size-fits-all approach has produced a general-purpose operating system that has grown from 16 million lines of code in Version 4.0 to 30 million in Version 5.0. In their hurry to create an operating system that competes with Unix, NT developers have been inefficient in implementing their design, Goguen says.
The current version of the more mature and streamlined Solaris is a relatively lean 10 million lines of code. "So it's easier for us to maintain our code,'' Goguen says. "In terms of reliability, having less complexity is like having fewer moving parts.''
There is no facility in NT that tracks misbehaving applications and prevents memory leaks. Consequently, these applications may steal more and more memory until the system crashes.
But such interruptions aren't an option in a high-availability enterprise server. Unix can spot faulty programs before they crash and continue to provide uninterrupted service to other applications even if they do. And Unix applications are less likely than their NT counterparts to cause trouble in the first place.
"Unix programmers and application architects tend to have more experience developing applications that are highly durable and supportable in a multiuser network environment,'' says Terrell Jones, CIO for The Sabre Group Holdings, Inc., a travel services company in Ft. Worth, Texas.
Sabre has two big travel applications - one on NT and one on Unix. "For speed and scalability, Unix remains the choice,'' Jones says. "And NT probably has a higher operational cost because of its hardware requirements and complexity. But we're happy with NT security.''
Safety in numbers
Microsoft last year addressed reliability by adding its ambitiously named Cluster Server software. Two NT servers can be linked to provide redundancy in case of a failure. However, the software doesn't provide a single-system image, and failover recovery takes 30 to 60 seconds. Nor do the two servers do load balancing, which means that a lot of system resources are being wasted. NT 5.0 will improve on this by supporting clusters that scale beyond two servers and perform load balancing.
Meanwhile, managers can use NT in a zero-downtime environment with the help of some third-party technology. The Chicago Stock Exchange (CSX) has a fully redundant NT network that runs its trading floor and processes more than 1,000 messages per second. The number of concurrent users stands at 130 today and is expected to increase to 300 in the next year. The NT-based network is a mission-critical platform that supports real-time transactions and must be available 100% of the time when the market is open.
"For everything below the enterprise database level, availability is not an issue with NT if you select the right products and design and implement an appropriate fault-tolerant architecture,'' says Steve Randich, CIO at CSX. The CSX trading floor application is based on the Versant object database from Versant Object Technology Corp., of Fremont, Calif. The company has a Versant Fault Tolerant Server version that protects the CSX application from NT or hardware failures.
"Memory leaks were a problem at first, but they have been largely resolved by working with developers on fixes that make the applications behave properly," Randich says. "And the NT servers are rebooted after the market closes each day, so we free up consumed memory.''
There's more to availability than clustering. Equally important are management facilities that provide advanced diagnostics, a global directory, remote administration and online serviceability. "This is where NT is way, way behind,'' says Hurwicz of the Patricia Seybold Group. "There is still a lot that needs to be done.''
For one thing, NT must become a good corporate citizen. It is coming into enterprise environments in a junior position and has to be managed by the senior machines in the hierarchy. "Microsoft always assumes its software is in the senior position, and in reality, it's not,'' says IDC's Kusnetzky. "That's been the real trial for implementers - making NT fit in and be manageable.''
Misbehaving applications cause most of the availability problems. The core NT technology appears to be quite robust. Companies such as Berkeley Networks, Inc. and PulsePoint Communications have chosen NT as the operating system for next-generation data switches and carrier-grade telecommunications switches.
"We use NT in a turnkey, black-box fashion,'' says Donal Byrne, vice president of marketing for Berkeley Networks, of Milpitas, Calif. The company is set to release an applications-aware Gigabit Ethernet switch. "When you don't allow an arbitrary set of drivers or applications to be placed on top of NT, its uptime is very, very high.''
Getting past insecurities
While opinions differ, the gap between NT and Unix doesn't seem to be so wide when it comes to security. In fact, some think NT has an inherent advantage because security attributes were built into it from the ground up.
"From an architectural standpoint, this gives NT a huge advantage,'' says Andrew Lowe, a software architect for PSW Technologies, Inc., of Austin, and author of the book Porting Unix Applications to Windows NT.
But for the time being, Unix has a jump on security simply because of its proven track record.
Unix started off as a relatively insecure environment back in the ARPANet days; security features were added gradually as the government adopted the operating system and forced the issue. Kerberos was developed on Unix, and Unix vendors can now offer several levels of security.
However, users insist NT is quite secure, too, despite the recent rash of denial-of-service attacks on NT-based Web servers. Most of the victims weren't protecting their NT servers with firewalls, and all failed to install the fix Microsoft had published prior to the attacks. Not surprisingly, most security breaches are caused by faulty security administration.
"I'm happy with the security of NT relative to Unix,'' Jones concludes. "It's just a perception that NT security is weak. It hasn't been out there long enough for the security firms to tout it.''
NT 5.0's security features include Kerberos authentication, distributed password authentication and support for public- and private-key encryption. The CryptoAPI has been updated to help third parties create new encryption techniques, and the NT file system has been enhanced to support encryption at the file and directory levels on servers and workstations.
Operating system for the masses
One NT feature that gets touted is ease of use. While Unix is programmer-driven, Microsoft has always focused on making things easier for users. NT's network configuration is completely GUI-based and the majority of IS professionals are more comfortable in Windows than in Unix.
"You can't get good Unix people, and retaining the ones you have is also a problem,'' says Edward Simmons, vice president of distributed architecture for Merrill Lynch & Company, Inc., of Plainsboro, N.J. "That's a big reason for our push into NT. It uses an object model, the setup is easier and there aren't different flavors of it. All NT is the same.''
However, NT's entry point is so low that it is causing problems with some big NT rollouts.
"NT's greatest strength is also its greatest weakness,'' says Nina Lytton, president of Open Systems Advisors, Inc., an IT consultancy in Boston. "The first rung of the ladder is so close to the ground that anyone can get on it.''
Many administrators have a desktop or workgroup orientation and lack the enterprise skills they need to deploy NT on a large scale. Some try anyway and make a mess, and the failures get chalked up to NT scalability problems. "We're seeing a lot of problems in NT deployments that have nothing to do with technology and everything to do with lack of skills and proper management,'' says Tom Bittman, research director in charge of the NT and mid-range systems group at Gartner Group, Inc., in Stamford, Conn. "People who don't have an enterprise perspective are pushing NT too far in terms of scalability and reliability.''
Ultimately, NT's success vis-…-vis Unix depends on application support. Microsoft has always been great at rallying independent software vendors (ISV) around the Wintel platform, and users and analysts agree the behemoth made a lot of progress this year.
"The last time we saw this kind of major investment in application development was when Windows 3.0 first came out,'' Kusnetzky says. Enterprise-level software developers, such as Oracle Corp., SAP AG, PeopleSoft, Inc. and The Baan Co. N.V., are moving aggressively into the NT space. So are smaller players.
"The third-party software developers are much more comfortable in the NT environment today,'' says CSX's Randich. "We use Orbix from Iona [Technologies PLC, of Cambridge, Mass.] for our object request broker, and it was a bit rickety on NT a year ago. But Iona has stabilized it and added some rich features.'' CSX had a similar experience with its Versant object database.
In the enterprise resource planning arena, NT now accounts for nearly half of all of SAP AG's unit sales of SAP - up from zero in 1995. "SAP is one of the most demanding applications in the galaxy, with single transactions touching multiple database tables,'' Microsoft's Muth says. "No one has yet built a computer big enough to consider SAP a trivial workload.'' IBM last month gave NT a big vote of confidence when the systems giant announced the porting of IBM's TXSeries transaction-processing middleware to NT. It is being bundled into a high-end software suite, code-named Bartoldi, that comprises ADSM, DB2 Connect and DB2 Universal Database, Network Communi-cations Server and systems management links to Tivoli Systems, Inc.
"These are the crown jewels, and IBM is bringing them to NT,'' Hurwicz says.
Clearly, the same economic weapons that won Microsoft the desktop - commodity hardware and ease of use and development - are rapidly securing for NT the crucial middle tier, where most business-logic programming takes place. Microsoft's success here is forcing even the most committed Unix shops to deploy some NT servers. One is Nicholas-Applegate Group, an investment banker in San Diego. The company would rather stick strictly to Unix, but it isn't possible anymore. "Microsoft is definitely getting the middleware,'' says David Buckley, global Unix systems manager for Nicholas-Applegate. "It's why we're running a few things on NT.''
A matter of time
To move into the top tier of the enterprise application arena, Microsoft needs to scale its business model up alongside NT. The company is geared toward selling millions of cheap desktop units anonymously through a distribution channel. In the Unix market, a single enterprise system might cost $5 million and would involve an ongoing service and support relationship with the customer.
For now, "it is frankly not our goal to compete with the top 1% to 2% of scalable systems,'' says Mark Hassel, NT server product manager at Microsoft.
Meanwhile, count on the Unix community to keep raising the technological bar.Much of what ails NT is simply its age. Unix has been maturing for decades while 5-year-old NT is barely out of the toddler stage.
"NT is a good body of code with good features, but it has to be out there much longer before people can really analyze its behavior in an enterprise environment,'' PSW's Lowe says. |
