Why use UNIX?

[kidlinux]

I've heard people say that UNIX, like Solaris, AIX, HPUX, IRIX, is better than GNU/Linux. You would hope so, considering UNIX costs money but GNU/Linux is free! But recently I hear about all the big UNIX companies like Sun, IBM, HP and SGI, pushing GNU/Linux over UNIX. In fact SGI just made 128 processer GNU/Linux system called Altix. GNU/Linux just got o(1) scheduler too. Doesn't this mean GNU/Linux is more scalable than UNIX now? It seems all the big UNIX companies want to standardize on GNU/Linux, which is good! But why do people still say UNIX is better?

[highwizard]

I've heard people say that UNIX, like Solaris, AIX, HPUX, IRIX, is better than GNU/Linux. You would hope so, considering UNIX costs money but GNU/Linux is free! But recently I hear about all the big UNIX companies like Sun, IBM, HP and SGI, pushing GNU/Linux over UNIX. In fact SGI just made 128 processer GNU/Linux system called Altix. GNU/Linux just got o(1) scheduler too. Doesn't this mean GNU/Linux is more scalable than UNIX now? It seems all the big UNIX companies want to standardize on GNU/Linux, which is good! But why do people still say UNIX is better?

Honestly, I believe it is for the same reason that people say Windows is better then Linux.... Personal Preference.

[bascule]

I've heard people say that UNIX, like Solaris, AIX, HPUX, IRIX, is better than GNU/Linux. You would hope so, considering UNIX costs money but GNU/Linux is free! But recently I hear about all the big UNIX companies like Sun, IBM, HP and SGI, pushing GNU/Linux over UNIX.

Sun is still pushing Solaris on the server. They primarily intend Linux to be used for desktop systems.

In fact SGI just made 128 processer GNU/Linux system called Altix.

128 is a large, albeit not unheard of, number of processors for a single system image. Rest assured that the Linux kernel running on these systems has been heavily modified by SGI to do so, and that the changes they have made to allow this degree of scalability would not apply to other architectures without a considerable amount of work. I'm certain much of the code they're using to allow this originally came from Irix, so it's really just the best of both worlds.

GNU/Linux just got o(1) scheduler too. Doesn't this mean GNU/Linux is more scalable than UNIX now?

Not at all. Solaris, for example, has had an O(1) scheduler for over half a decade. As far as scalability goes, Linux is still playing catchup. Solaris has a fully modular scheduler subsystem which allows multiple schedulers to run simultaneously, and for new schedulers to be loaded/unloaded on the fly, as well as for processes to be migrated between different schedulers. For use on large systems, Linux typically needs to be patched to support high-end resource partitioning features. As far as I know, there's still no process group implementation for Linux, and no Fair Share Scheduler implementation. Timeshare schedulers are not ideal for large systems as they allow users to easily monopolize system resources as they typically provide system administrators with little control over how resources are consumed on the system.

It seems all the big UNIX companies want to standardize on GNU/Linux, which is good! But why do people still say UNIX is better?

That does seem to be the way the wind is blowing. Just don't expect Sun to start pushing Linux instead of Solaris on the server any time in the near future.

[Chris]

Also, there is the matter of legacy hardware. Large organizations have invested millions of dollars in their hardware (Sparc, Origin you name it) and simply cannot afford to scrap it all for a new architecture.

I know of a major insurance company that still runs it's entire business off of IBM 360/370s because they aren't willing to upgrade the hardware and software. It was cheaper for them to pay a lot, and I mean A LOT, of money to have the Y2k isssues addressed (and yes with 360/370 it was a REAL issue) than upgrade.

There is also something to be said for an OS that is developed specifically for the hardware a system uses (Mac fans stand up and be counted here).


That said, in most situations these days, if I was going to add new hardware to an existing architecture, or build a new architecture from the ground up, I would go with Linux. Most, I say, not all.

[bascule]

That said, in most situations these days, if I was going to add new hardware to an existing architecture, or build a new architecture from the ground up, I would go with Linux. Most, I say, not all.

Agreed. If you were, say, developing the backend for a database-driven JSP web site, Linux would be an excellent choice for the application servers, but for the database servers you are more than likely going to want Oracle/Solaris (a 64-bit architecture is important because otherwise the DBMS has to process data in a maximum of 4GB chunks due to addressing limits of 32-bit architectures) The V440, for example, provides excellent price/performance even when compared with commodity x86 systems from Dell. Reliability is an important concern with database servers as well... chances are you will only be replicating the database across a small number of servers (2-4), so losing one dramatically impacts database performance and thus overall performance of the web site. The cost of even a small amount of downtime might greatly outweigh the cost difference between a commodity x86 server and a Sun server. These are all issues which must be properly evaluated when making purchasing decisions.

[Chris]

Agreed. If you were, say, developing the backend for a database-driven JSP web site, Linux would be an excellent choice for the application servers, but for the database servers you are more than likely going to want Oracle/Solaris (a 64-bit architecture is important because otherwise the DBMS has to process data in a maximum of 4GB chunks due to addressing limits of 32-bit architectures) The V440, for example, provides excellent price/performance even when compared with commodity x86 systems from Dell. Reliability is an important concern with database servers as well... chances are you will only be replicating the database across a small number of servers (2-4), so losing one dramatically impacts database performance and thus overall performance of the web site. The cost of even a small amount of downtime might greatly outweigh the cost difference between a commodity x86 server and a Sun server. These are all issues which must be properly evaluated when making purchasing decisions.

Excellent example. Solaris/Oracle should come up with one of those spiffy nicknames like Wintel they are so tightly integrated. Solaracle? Oralis?

[kidlinux]

Okay thanks for the infoz. I have never talked to a real UNIX person or even seen a UNIX machine before, and the GNU/Linux people I talk to make it sound like GNU/Linux is already better than UNIX, but it sounds like UNIX still has some tricks in its bag.

[jesse]

A good analogy would be that Linux works like a van or semi-truck. Solaris is used howerver, when you need an Aircraft Carrier.

[skroo]

A good analogy would be that Linux works like a van or semi-truck. Solaris is used howerver, when you need an Aircraft Carrier.

This is a good analogy. One thing that people need to remember in their fervour to zealously convert the whole world over to Linux (not saying that you are, kidlinux, just making a point) is that it is not always the best choice for all environments. Part of this is due to restrictions imposed when working under the x86 architecture; other considerations are financial or practical (can my staff use it, can the developers build for it, will it integrate cleanly with what we already have). And this is without getting into the question of who will support it when it breaks - if my E10K or RS/6000 catches fire, I can call Sun or IBM and they'll send out an engineer to pee on it. But if Slackware takes a dump all over my distributed database server, it's pretty unlikely that Linus Torvalds will be showing up at my office anytime soon to sort it out.

[hackajar]

It is also good to note that Linux did not come directly from the Unix food chain, but was inspired by it (almost exact command syntax is used in GNU apps).

Unix has been around since the beggining of time, therefore alot of the 'big thinker' concepts (see works by Tanenbom (sp?)) have been applied making Unix flavors stable and well groomed. This puts an idea of stablity in most administrators minds (is it 'sexy' versus does it work). Although they did not (do not) have the might of an open source community, so Linux plays catch up very quickly.

Bottom line, it's not 'which is better' or 'why use Unix' but rather 'which network OS will give me the most for what I want to do'

This comes directly from a corporate stand point. And so call'ed 'Avangelist' have to use this angle if they truly feel that there power house OS can stack up to that order (corporate sign off's).

[skroo]

It is also good to note that Linux did not come directly from the Unix food chain, but was inspired by it (almost exact command syntax is used in GNU apps).

An interesting (if understandably somewhat convoluted) graphical timeline of various *nices: http://www.levenez.com/unix/ . For those searching for the origins of Linux, see August 1, 1991, where it was essentially (though I feel not entirely accurately) spun off from Minix nearly a full 20 years after the release of Bell Labs' Unix.

[noid]

Not bad, they even mention AIX PS/2 (yup, x86 based AIX for the Model 70 and 80) and AUX