Many of you may have heard all sorts of things about Intel’s Larrabee, lately. While a lot of it is rather nonsensical and conjecture at this point, I’m here to shed some light on the subject.
Firstly, Larrabee is the end result of the latest trend toward using GPUs as a general-purpose solution. It’s a massively-parallel piece of silicon, and is rather unlike any graphics card that precedes it. At the moment, Larrabee is set to be released late this year with 32 cores, a dual-ring bus architecture connecting everything together, and a lot of other fine details that set it apart from its competitors. What we can expect is a new card that brings parallel processing to the fore at a relatively cheap price, and something that could very well change the way our games and graphical applications are coded. Yes, it’s going to be a PCI-E card; yes, it will require external power for the high-end versions; and yes, it will be expensive.
One thing that puts Larrabee in the spotlight is Intel’s decision to use the x86 instruction set. The inclusion of the most vital instruction set in the history of computing means that coding a game for Larrabee will be a relatively easy task. With the PS3’s cell, developers have to use two sets of code for the game, making it time-consuming and confusing, but with x86 it should be a linear affair. Memory management will also be much simpler, with every single byte of memory available to the processors. Therefore, coding for Larrabee will be much like coding for a CPU, with a twist.
Larrabee introduces a change in the use of cache memory by prioritizing code and the requisite data, avoiding the problem of filling up the cache with useless information. To speed things up, SMT (simultaneous multi-threading) is used in all the cores, as well as the use of a Mask Register to predict the results of a thread using parallel processing, and only forward the correct end result to be rendered on the screen (which allows for some clever use of code to do interesting things).
So here we have a GPU with the flexibility of a CPU, and Larrabee is certainly capable of running an OS all on its own. Its functionality is limited by the software in use, so advancements in the API Larrabee uses could unlock further potential in the future. It really looks like a killer, but let’s keep our excitement in check.
As gamers, we are all familiar with the hype engine, and we are all familiar with the possibility of unfulfilled expectations. On paper, it looks really good, but in reality it may not catch on so quickly, and it might even prove to be another failure. Certainly, Larrabee will breathe some fresh air into the industry, but don’t hold your breath hoping it sweeps you off your feet immediately.
Congrats to Intel’s lab monkeys, though, they really know how to make people swoon over hardware!