Re: Filesystems (was My First Computer)

[jeffj@panix.com (Jeff Jonas)]

>> Or you can find someone getting rid of an AIX box
>IBM is dumping the whole operating system, not just one AIX box...
>http://zdnet.com.com/2100-1104-982512.html

I have mixed feelings about all this.

I'm a Linux user and advocate, but moreso I advocate
diversity and choice in technology too.
I never wanted to use VMS or OS/2 or Amiga or Apple ...
but I was happy to know that there were alternatives available.
Malware (virus, worms, trojans, ...) thrives on the monoculture of
operating systems.  It was once an ADVANTAGE for a company to have
a speciality, a niche market that it really understood.

I consulted to IBM for an AIX project.
IBM fostered a horrible "not invented here" mentality.
IBM had hired Convergent to make 2 AIX ports:
for the PS/2 and the 3090 mainframe.
They were tightly coupled into clusters and the TCF (totally confusing facility).
No matter how much I wanted to dislike AIX,
I saw many merits and unique features.
I suspect that IBM killed that project (even though they owned it and PAID for it)
since they wanted to re-invent it all with "native" code.
Surprisingly, AIX for the Risc-6000 succeeded since it was written
by the Austin Texas facility and was apparently exempt from the NY politics.

IBM gave up on OS/2 way too early, now they're giving up on their
flagship product just like DEC gave up on VMS?
Is this to say that NOBODY can do decent OS research anymore?

I worked at Concurrent Computer Corporation in 1989 when they
were the best in Real Time Unix, particularly after merging with
Masscomp for their smaller systems and real time expertise
[sadly, the merger destroyed both companies].
They modified the Unix file system for real time requirements
and they were not afraid to design their own hardware and integrate it
to the OS [many things that are now common were leading edge then:
an independent microprocessor "front panel" monitoring the temperature,
voltages, fan tachometers; things now built into PC motherboards!]
There were many opportunities for OS research and enhancements back then.
Now, just try to find a fully supported real time OS from anyone :-(



re: file systems vs O.S.:
I worked at AT&T Information Systems on System V Release 4.0.
That's when AT&T & Sun microsystems kinda merged their
Unix systems with a technology trade.
Before SVR4.0, the disk filesystem was rather hard-coded into the kernel
and utilities, so RFS was kinda bolted-on as an afterthought.
(the "File System Switch" was a first step: it let you add other file systems
so long as they APPEARED like a Unix file system at the software interface).

The VFS (Virtual File System) gave a level playing field for any file system to
link into the system since it was a table of functions for EVERYTHING
(mount, unmount, read, ...).  No more "native" vs "foreign" code.
Back then there were a handful of file systems to choose from
(the "traditional" System V, the Berkley Fast File System,
Veritas journaling systems, RFS, NFS, ...).
Virtual file system started to appear too (/proc).

Linux has GREATLY accelerated the state of the art with more
file system types available than you can shake a stick at!
While some are still read only or experimental,
many are fully supported so they can be used for ANY of the file systems,
not just "foreign" data.
It's a joy to keep finding more file system types
and how they just plug in and work right away!

How many years will it take for M$ to "reinvent" this technology too
so they can wean folks away from the FAT filesystems?
-- 
Jeffrey Jonas
jeffj@panix(dot)com
The original Dr. JCL and Mr .hide