5 ms·

Unless I missed something, the article does not concretely state what the VAX is.

by blt 5y ago

vaxman 5y ago
The TL;DR is that the VAX was the first and most powerful line of 32-bit computer systems ever developed, the culmination of 20 long years of work by the world's best team of computer scientists (at DEC) competing day and night against the world's second best team of computer scientists (at Data General). On a technical level, the VAX platform came under attack when Sun Microsystems (now Oracle) brought out the more limited, but much faster, RISC-based SPARC architecture (that no CISC based architecture, even the VAX, could compete with) running UNIX (that lacked decades of advancements made by the VAX's operating system, VMS). DEC's elite team responded to Sun's SPARC with its 64-bit Alpha architecture, but DEC was allegedly betrayed when DEC showed Intel the design for its new Alpha chips so that Intel could evaluate whether to become a "second source" producer of Alpha chips and their revolutionary new design wound up in something called the "Intel Pentium Pro" that suddenly and unexpectedly revived the all but dead 808x architecture (that even Microsoft had spent millions porting Windows away from). Intel has been unable to create a viable successor so today we have 11th generation Core i9 whereas even Apple has moved on to its own chips (that ironically are licensed from what is the descendant of DEC's other architecture, called StrongARM). DEC's lead operating system engineer for the VAX (Dave Cutler) had already jumped to Microsoft and suddenly Microsoft now had access to an 808x-compatible chip as powerful and scalable as DEC's proprietary Alpha chip and the rest is history. While DEC settled the allegations against Intel, DEC never really recovered financially and wound up being acquired by Compaq and destroyed by the CEO of its long time nemesis HP, as HP acquired Compaq.
- Animats 5y ago
  (Intel) "second source" producer of Alpha chips and their revolutionary new design wound up in something called the "Intel Pentium Pro" that suddenly and unexpectedly revived the all but dead 808x architecture. No. The Alpha was a RISC machine. The Pentium Pro was a demonstration that, with 3000 engineers at peak, you could actually get several instructions per clock out of x86. It was the first real superscalar microprocessor, one where what the CPU is doing inside is very different from what the programmer sees as the instruction set. The VAX was a classic CISC machine. Way too complex an instruction set. Amusingly, x86 turned out to be a good instruction set for superscalar machines. Not too many registers, so context switches were not so bad. Variable length instructions, so you didn't get "RISC bloat", which tended to double the size of code and cause cache misses. The fast but dumb one-instruction-per-clock RISC CPUs were outclassed by superscalar x86. You can build superscalar RISC machines, but once you've added a few hundred million transistors of superscalar logic, you've lost any simplicity advantage RISC offered.
  - vaxman 5y ago
    Intel settled the lawsuit (over DEC's Alpha tech winding up in PentiumPro) by agreeing to purchase DEC's Hudson division (that produced Alpha and StrongARM chips).
    - vaxman 5y ago
      https://www.cnet.com/tech/services-and-software/intel-digital-settle-suit/ https://www.cnet.com/tech/services-and-software/intel-digita...
- jandrese 5y ago
  > unexpectedly revived the all but dead 808x architecture The Pentium Pro came out in 1995. To say the x86 architecture was "all but dead" at that point is not supported by the historical record.
  - vaxman 5y ago
    Not sure what dates the history books say (never had time to read them because, you know, living it), but Pentium Pro was known to exist well before 1995. Even Intel had been pushing their two other processor lines, the i860 and the iAPX 432, as "successor" to the ailing 808x and, as I wrote in the post, Dave Cutler's Windows NT team at Microsoft was buy getting their bits running on MIPS and other processors (out of fear that they would be blown off out of the water by Unix running machines much faster than the 486/586-aka-Pentium processors). It's okay, Linux and guys like Mad Dog eventually got 'em (with license-free hardware-neutral software), though Apple (and the M1) are getting the last laugh.
- cstross 5y ago
  ARM was originally Acorn RISC Machines, a spin-out from British computer firm Acorn, who set it up in conjunction with Apple (who wanted a low-power RISC cpu for the Newton): Acorn produced the RISC PC as a successor to the BBC Model "B" family of 8-bit 6802-based micros that were popular in the UK, but failed to compete effectively against Amiga and Atari ST or to move up into the workstation market. In the end, Acorn ended up supplying TV set-top boxes and faded out. But ARM exists to this day, and they are the folks who license the ARM instruction set to customers including Apple. SPARC had nothing to do with ARM, but was entirely Sun's own RISC project, and an attempt to find a way off Motorola CPUs (which powered Sun's earlier workstations).
  - vaxman 5y ago
    ARM cores today descended from StrongARM, which was a joint venture between DEC and ARM. What I said was that DEC's Alpha project was a response to SPARC to save the VAX market. The StrongARM project was unrelated.
tyingq 5y ago
It would have been helpful if it mentioned things like VAX clustering, versioned files, built-in KV store (indexed files), and so on.
cbm-vic-20 5y ago
Near the end of the 1970s, DEC PDP-11 customers were reaching the limit of what the PDP-11 architecture could support: PDP-11 is a 16-bit architecture: the first generation could address a whopping 56kb of memory (the top 8kb of the memory map was for I/O). Over time, extensions were added to extends that out to 18 bit addressing, and finally 22 bit, for a total of 4Mb. But programs could still only directly address 16-bit chunks at a time, and would have to twiddle the memory management hardware to access other chunks. VAX was the "Virtual Address eXtension" to PDP-11, which was released right around 1979/1980, was a 32-bit architecture, and additional processor instructions. VAX ended up being a much different beast, but you could still see that it was extended from the PDP-11 platform. DEC made a lot of tooling to make the transition from PDP-11 to VAX as smooth as possible for developers- they provided compilers that were source-compatible, etc., for FORTRAN, COBOL, C, BASIC, etc.
dboreham 5y ago
Shakes head that I'm now in a world where someone has to explain what a VAX is...

Unless I missed something, the article does not concretely state what the VAX is.

by blt 5y ago

Unless I missed something, the article does not concretely state what the VAX is.

The TL;DR is that the VAX was the first and most powerful line of 32-bit computer systems ever developed, the culmination of 20 long years of work by the world's best team of computer scientists (at DEC) competing day and night against the world's second best team of computer scientists (at Data General). On a technical level, the VAX platform came under attack when Sun Microsystems (now Oracle) brought out the more limited, but much faster, RISC-based SPARC architecture (that no CISC based architecture, even the VAX, could compete with) running UNIX (that lacked decades of advancements made by the VAX's operating system, VMS). DEC's elite team responded to Sun's SPARC with its 64-bit Alpha architecture, but DEC was allegedly betrayed when DEC showed Intel the design for its new Alpha chips so that Intel could evaluate whether to become a "second source" producer of Alpha chips and their revolutionary new design wound up in something called the "Intel Pentium Pro" that suddenly and unexpectedly revived the all but dead 808x architecture (that even Microsoft had spent millions porting Windows away from). Intel has been unable to create a viable successor so today we have 11th generation Core i9 whereas even Apple has moved on to its own chips (that ironically are licensed from what is the descendant of DEC's other architecture, called StrongARM). DEC's lead operating system engineer for the VAX (Dave Cutler) had already jumped to Microsoft and suddenly Microsoft now had access to an 808x-compatible chip as powerful and scalable as DEC's proprietary Alpha chip and the rest is history. While DEC settled the allegations against Intel, DEC never really recovered financially and wound up being acquired by Compaq and destroyed by the CEO of its long time nemesis HP, as HP acquired Compaq.

Animats 5y ago
(Intel) "second source" producer of Alpha chips and their revolutionary new design wound up in something called the "Intel Pentium Pro" that suddenly and unexpectedly revived the all but dead 808x architecture. No. The Alpha was a RISC machine. The Pentium Pro was a demonstration that, with 3000 engineers at peak, you could actually get several instructions per clock out of x86. It was the first real superscalar microprocessor, one where what the CPU is doing inside is very different from what the programmer sees as the instruction set. The VAX was a classic CISC machine. Way too complex an instruction set. Amusingly, x86 turned out to be a good instruction set for superscalar machines. Not too many registers, so context switches were not so bad. Variable length instructions, so you didn't get "RISC bloat", which tended to double the size of code and cause cache misses. The fast but dumb one-instruction-per-clock RISC CPUs were outclassed by superscalar x86. You can build superscalar RISC machines, but once you've added a few hundred million transistors of superscalar logic, you've lost any simplicity advantage RISC offered.
- vaxman 5y ago
  Intel settled the lawsuit (over DEC's Alpha tech winding up in PentiumPro) by agreeing to purchase DEC's Hudson division (that produced Alpha and StrongARM chips).
  - vaxman 5y ago
    https://www.cnet.com/tech/services-and-software/intel-digital-settle-suit/ https://www.cnet.com/tech/services-and-software/intel-digita...
jandrese 5y ago
> unexpectedly revived the all but dead 808x architecture The Pentium Pro came out in 1995. To say the x86 architecture was "all but dead" at that point is not supported by the historical record.
- vaxman 5y ago
  Not sure what dates the history books say (never had time to read them because, you know, living it), but Pentium Pro was known to exist well before 1995. Even Intel had been pushing their two other processor lines, the i860 and the iAPX 432, as "successor" to the ailing 808x and, as I wrote in the post, Dave Cutler's Windows NT team at Microsoft was buy getting their bits running on MIPS and other processors (out of fear that they would be blown off out of the water by Unix running machines much faster than the 486/586-aka-Pentium processors). It's okay, Linux and guys like Mad Dog eventually got 'em (with license-free hardware-neutral software), though Apple (and the M1) are getting the last laugh.
cstross 5y ago
ARM was originally Acorn RISC Machines, a spin-out from British computer firm Acorn, who set it up in conjunction with Apple (who wanted a low-power RISC cpu for the Newton): Acorn produced the RISC PC as a successor to the BBC Model "B" family of 8-bit 6802-based micros that were popular in the UK, but failed to compete effectively against Amiga and Atari ST or to move up into the workstation market. In the end, Acorn ended up supplying TV set-top boxes and faded out. But ARM exists to this day, and they are the folks who license the ARM instruction set to customers including Apple. SPARC had nothing to do with ARM, but was entirely Sun's own RISC project, and an attempt to find a way off Motorola CPUs (which powered Sun's earlier workstations).
- vaxman 5y ago
  ARM cores today descended from StrongARM, which was a joint venture between DEC and ARM. What I said was that DEC's Alpha project was a response to SPARC to save the VAX market. The StrongARM project was unrelated.

tyingq 5y ago

It would have been helpful if it mentioned things like VAX clustering, versioned files, built-in KV store (indexed files), and so on.

cbm-vic-20 5y ago

Near the end of the 1970s, DEC PDP-11 customers were reaching the limit of what the PDP-11 architecture could support: PDP-11 is a 16-bit architecture: the first generation could address a whopping 56kb of memory (the top 8kb of the memory map was for I/O). Over time, extensions were added to extends that out to 18 bit addressing, and finally 22 bit, for a total of 4Mb. But programs could still only directly address 16-bit chunks at a time, and would have to twiddle the memory management hardware to access other chunks. VAX was the "Virtual Address eXtension" to PDP-11, which was released right around 1979/1980, was a 32-bit architecture, and additional processor instructions. VAX ended up being a much different beast, but you could still see that it was extended from the PDP-11 platform. DEC made a lot of tooling to make the transition from PDP-11 to VAX as smooth as possible for developers- they provided compilers that were source-compatible, etc., for FORTRAN, COBOL, C, BASIC, etc.

dboreham 5y ago

Shakes head that I'm now in a world where someone has to explain what a VAX is...