Andrei POPESCU <[email protected]> wrote: > On Du, 14 mar 21, 07:19:25, The Wanderer wrote: >> When 64-bit came along, rather than extending the x86 line, Intel >> started from scratch and designed an entire new CPU architecture. >> That got called ia64, and it never caught on; it eventually failed in >> the marketplace, except possibly in very limited market segments. >> when Intel created a 64-bit architecture (called ia64), it turned out >> to be a developmental dead end and failed in the marketplace.
> As far as I recall from articles at the time, there were good reasons > to use the opportunity of the transition from 32 to 64 bits to create > a completely new architecture. > Regardless of the merits (or not) of the ia64 architecture, Intel > simply tried to force the industry to follow its lead, at significant > additional costs (see RAMBUS), but the industry chose amd64 instead. IA64 (Itanium) was completely incompatible with the installed i386 base. The first CPUs had a (very slow) compatibility layer, assisted by software, so you could run your "legacy" 16bit/32bit applications. Also the CPU was designed so that many complexities where delegated into the compiler to create the most optimal code but the compilers at the time where not up to the task, greatly hampering the new architecture. Intel envisioned IA64 to be the go to processor for centralized server-based loads, whereas the i386 was for your on-the-desk PC. (Just like at the start of the IBM PC it was enivsioned as a kinda-smart terminal for the mainframe. The SysRq-Key is the last remnant of that legacy.) Note: when IA64 was designed (starting in 1994 at HP) we where nowhere near the limits of the 32bit i386 architecture with RAM and frequency, so it made sense, somewhat. But years passed and the i386 architecture got better and better, including stuff like MMX, SSE and AVX was incorporated, IA64 couldn't really keep up. Dnd when AMD then presented their AMD64 architecture that could run legacy 8bit/16bit/32bit code as fast as the new code, allowing for a smooth transition, the nickname "Itanic" for IA64 became true: It had been dead on arrival. S° -- Sigmentation fault. Core dumped.
