The genius of the itanium

The final shipment of itanium chips went out a few weeks ago now, and that got me thinking about it again.

So I’ve spent most of the past 20 years championing the Itanium because it is truly brilliant. The basic design idea of taking the trying-and-optimize-the-paralellism-of-the-code that was in the processor and putting it in the compiler was brilliant. No question. I think the real reason it didn’t take off was sure, because the compilers were hard to write but so was monopoly at some point, that would eventually get worked out. Really, I think it was because the first itaniums didn’t run windows very well. Oh well, too bad, that’s history now.

But recently when I started thinking about it again and now knowing what the future turned out to be, it turns out the Itanium, though brilliant at the time was really just a stopgap.

They eventually would have squeezed all the performance possible out of the super wide instructions on the itanium, and maybe they’d find ways to expand the wide instructions and make them extra super wide or mega wide, but at the end of the day, they’d still be left with the 4ghz problem. One core can only go so fast.

Now that we see the future, we know that the world moved to parallel processing which any processor can do and all the added complexity of the Itanium would just have been a big technical burden to carry forever on. So maybe the lack of adoption was for the best after all. sure there are crazy optimizations on the x86 chips, which are now also biting us in the ass (spectre, etc) so maybe it would have turned out the same way in either case.

But my point is, I spent years marvelling at the wonders of this novel chip design and in the end, it wouldn’t really have bought us much, because like a lot of intended futures, things actually end up going off in a wildly different direction than anybody could have anticipated.

Same thing with ZFS. I love zfs, it’s amazing, but it was designed in a time when we thought we’d be adding more and more disk to a single machine. The future didn’t quite turn out that way did it. So now zfs is amazing for what it is, but it just can’t compete with an entire cloud of storage.

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