I seem to remember that Alpha’s were very fast for the time but their maximum optimization level waived IEEE floating point conformance. This, of course, drove us nuts trying to validate ports of numerically intensive code. Less interesting chips with lower optimization and limited market penetration.
Now, HP’s PA-RISC chips…. Those things were fast and easier to work with. Curiously, with SoftPC they could do windows faster than a 486 could. Slaughtered all sorts of mini-supers they did.
Would have been interesting if alpha survived to compete with SGI’s MIPS.
I worked on the first PA-RISC workstations (“snakes”). PA-RISC started as a fairly pure RISC design and was consequently very simple and predictable (short pipeline, 1 delay slot, no complex instructions). The philosophy of the design team was to make the system fast with high clock speeds, short pipelines, and big caches, all big fundamental variables in the performance equation.
Alpha was much more sophisticated but also a lot more complex. The Alpha memory model, in particular, was quite complex with lots of cache control and barrier primitives, IIRC. But it could fly when you got the stars to align.
what did they not implement from 754? Given the design of the processor i can imagine them being very aggressive with assumptions around exception handling / traps - iirc this is actually the original reason why Tomasulo algorithm exists because the first out-of-order processors didn't actually make any guarantees about the order that you would observe these side effects.
> David Jessel, the Alpha's senior product manager, claims that Alpha fans have nothing to worry about. "Compaq has been fully supportive of the Alpha and is continuing to invest in it," Jessel said.
That worked out swimmingly for Alpha... >sigh<
I never programmed Alpha assembly, so I don't really have a feel for the architecture. I did deploy some Alpha-based boxes running NT, and they were very nice. They didn't feel pieced-together like x86 servers did.
Now, HP’s PA-RISC chips…. Those things were fast and easier to work with. Curiously, with SoftPC they could do windows faster than a 486 could. Slaughtered all sorts of mini-supers they did.
Would have been interesting if alpha survived to compete with SGI’s MIPS.
Alpha was much more sophisticated but also a lot more complex. The Alpha memory model, in particular, was quite complex with lots of cache control and barrier primitives, IIRC. But it could fly when you got the stars to align.
That worked out swimmingly for Alpha... >sigh<
I never programmed Alpha assembly, so I don't really have a feel for the architecture. I did deploy some Alpha-based boxes running NT, and they were very nice. They didn't feel pieced-together like x86 servers did.