WEBVTT 00:00:00.000 --> 00:00:06.080 Most computer enthusiasts know Intel for their famous x86 CPU architecture that powers most 00:00:06.080 --> 00:00:15.140 of today's desktops and laptops. But did you know that not so long ago, Team Blue actually tried to kill off x86 entirely? 00:00:15.140 --> 00:00:19.880 If you're not sure what I'm talking about, maybe the name I-tanium will ring a bell? 00:00:19.880 --> 00:00:27.120 Eh? Probably not for a lot of you. This was an all-new architecture and CPU brand from Intel that made its debut back 00:00:27.120 --> 00:00:32.960 in 2001, and was billed as being so efficient that it would just naturally come to dominate 00:00:32.960 --> 00:00:38.760 the market at some point. But these days, you can barely even buy an I-tanium CPU anymore. 00:00:38.760 --> 00:00:44.520 So what was the big idea? Let's start as we always do with a little bit of history. 00:00:44.520 --> 00:00:49.400 Back in the 1990s, Hewlett-Packard was looking at ways to make CPUs more parallel, but instead 00:00:49.400 --> 00:00:54.400 of sticking more cores onto a CPU or using hyperthreading, HP wanted to simplify the 00:00:54.400 --> 00:00:59.960 architecture by having software determine what order to execute instructions in, instead 00:00:59.960 --> 00:01:03.440 of having the CPU do the heavy lifting and hardware. 00:01:03.440 --> 00:01:07.760 The hope was that this would free up processing resources to execute more instructions in 00:01:07.760 --> 00:01:12.320 parallel, ultimately making for a more powerful, energy efficient CPU. 00:01:12.320 --> 00:01:17.560 HP took the new architecture, which was called Epic, no not that one, to Intel, which then 00:01:17.560 --> 00:01:23.120 helped develop it further into IA64, the architecture used in I-tanium. 00:01:23.240 --> 00:01:27.960 I-tanium was also Intel's first attempt at a 64-bit processor and actually hit the 00:01:27.960 --> 00:01:34.200 market before AMD's first 64-bit CPU, Opturon, which released in 2003. 00:01:34.200 --> 00:01:39.200 HP and Intel felt confident that I-tanium would become popular in the server and workstation 00:01:39.200 --> 00:01:44.160 settings and go on to overtake x86 in home PCs as well. 00:01:44.160 --> 00:01:48.480 There was even a version of Windows specifically written for I-tanium's architecture. 00:01:48.480 --> 00:01:55.320 So why did it flop so badly? So it turns out that trying to determine what instructions the CPU should run in software 00:01:55.320 --> 00:01:59.000 is a lot trickier than HP and Intel thought it would be. 00:01:59.000 --> 00:02:03.400 Typically, the CPU has a specialized group of circuits called a scheduler that determines 00:02:03.400 --> 00:02:09.400 what order to run instructions. The scheduler can make these decisions much more effectively than software can, since 00:02:09.400 --> 00:02:15.200 the scheduler can make adjustments based on when exactly the CPU is trying to access the memory. 00:02:15.200 --> 00:02:19.280 This can't be done effectively in software, since you can't figure out when the CPU is 00:02:19.320 --> 00:02:26.240 accessing memory ahead of time. And because the software would pre-schedule instructions, I-tanium CPUs suffer from stalls 00:02:26.240 --> 00:02:32.200 quite frequently, slowing them down. There was also the issue that even though I-tanium's architecture was intended to be the way of 00:02:32.200 --> 00:02:38.520 the future, Intel still had to do business in the present, and the vast majority of software 00:02:38.520 --> 00:02:45.120 for servers and workstations was written for x86 or other non-I-tanium architectures. 00:02:45.120 --> 00:02:49.240 Running these programs on I-tanium meant that they had to be emulated, which introduced 00:02:49.240 --> 00:02:57.080 a huge amount of performance overhead. And to make matters even worse for I-tanium, the aforementioned Opturon from AMD was released 00:02:57.080 --> 00:03:05.200 two years later. Although Opturon was also 64-bit, it used the X8664 instruction set, the same one that 00:03:05.200 --> 00:03:08.960 powers the chips that's probably sitting in your home PC right now. 00:03:08.960 --> 00:03:13.960 And as the name implies, it's natively compatible with x86 since it was essentially built on 00:03:13.960 --> 00:03:20.200 top of it. So the folks running x86-based servers and workstations had a far easier time upgrading 00:03:20.200 --> 00:03:27.000 to Opturon instead of I-tanium for their 64-bit fix, making Team Red's offering much more 00:03:27.000 --> 00:03:34.440 popular. Intel, quickly realizing that I-tanium wasn't going to catch on, instead implemented X8664 00:03:34.440 --> 00:03:39.240 into their own Xeon lineup of server processors, which went on to become very successful. 00:03:39.240 --> 00:03:44.520 So Intel actually let Xeon cannibalize the I-tanium lineup to a large extent, and I-tanium 00:03:44.520 --> 00:03:47.960 became relegated to niche markets only. 00:03:47.960 --> 00:03:52.480 Intel did actually keep developing new models of I-tanium chips until 2017, but despite 00:03:52.480 --> 00:03:56.800 the fact it hung on for quite a while, it never made up more than a small fraction of 00:03:56.800 --> 00:04:00.120 Intel CPU sales. So what's the lesson here? 00:04:00.120 --> 00:04:04.240 If you're trying to reinvent the wheel, make sure you have a car to stick that wheel on, 00:04:04.240 --> 00:04:07.640 or at least like a tricycle. 00:04:07.640 --> 00:04:17.160 We're not really good at metaphors.