Intel Larrabee 3 将更名为 Larrabee 2，11 月样卡 融合流水线无需双码路径

Edison

http://www.semiaccurate.com/2010/05/17/larrabee-3-now-larrabee-2/

Larrabee boards coming in November

Larrabee 3 is now Larrabee 2
Convergence in 2012
by Charlie Demerjian

May 17, 2010

Intel LogoMOST PEOPLE SIMPLY don't understand what Intel is trying to do with their Larrabee chip, and why Intel simply has to keep going with it. That said, it is not, as many speculate, dead, or even wounded, but has had a few setbacks.

As someone who has been following Intel's GPU efforts since long before anyone believed they were real, I can state unequivocally that Intel is deadly serious about the GPU game, or more importantly the post-GPU game. Having first heard the name Larrabee in a memo deciding the winners and losers of several different mini-core projects.  Then we began digging in to it's design and what it's supposed to be.  When we first pointed out that it was an x86 based 'post-GPU' chip, howls of disbelieving laughter ensued.

After a few demonstrations, Intel pulled the plug on the first Larrabee chip, but did not kill the project, not by a long shot. Larrabee, the project, is far from dead, you can even get one if you convince Intel that you have a good use for it. With backers like Paul Otellini, you can be sure the project is ongoing. From what SemiAccurate's sources have been saying, his support has been quite strong since long before the roadmap reshuffle.

That brings up the question of what will we get when Larrabee comes out, and more importantly, when? Short answer, converged pipelines and 2012. What that means takes a little bit of background.

When Larrabee was first greenlighted, our sources told us that it was a 16-core, 65nm chip that was meant for developers to get their feet wet, not for public use. It was a software development seed part, but if you wanted to hand Intel cash for one, they would take the money. From what we understand, this part never taped out, so we will call it Larrabee 0.

Larrabee 1, aka the part you have heard of, was beset by delays. By the time it was deprecated, it was well over a year and a half late. The first official release date to come our way was mid to late 2008.

Problems arose. Thee Ax steppings were pretty rough, so rough that performance was less than 1/4 of it's intended targets, and power was through the roof. These bugs hampered development by compounding problems, and caused serious development setbacks. The root problems may have identified, but were not fixed until it was far too late.

The B0 stepping did fix the vast majority of the problems, but it didn't come back until late 2009. This pushed the release date out to Q2, basically now. For a chip that was targeting the HD4870/GTX285 generation of GPUs, a year's delay meant that it would be facing the HD5870/GTX285, one of them moving the bar up substantially.

Given the performance deficit, Intel was faced with a tough choice, pull the plug on the consumer part and take Pro-Averbial sh*tstorm of criticism from those not in the loop, or soldier on. Soldiering on meant Larrabee 2, 3 and 4 would probably be delayed as resources were diverted to get Larrabee The Elder out, and Intel would be chasing it's tail for a long time to come. Wisely, Intel pulled the plug on Larrabee 1 and 2, and refocused on Larrabee 3.

While armchair quarterbacks are not shying from criticism, this call shows Intel management is thinking long term, not appeasing the people looking for shiny things right now. It took quite a bit of guts to do, and announcing it publicly took even more. Kudos to Intel there, they could have just let it slip and hoped no one noticed.

That brings us to Larrabee 2, basically a refresh and cleanup of Larrabee 1. Tie up loose ends, optimize what they could, and fix whatever low hanging fruit that remained. It was a tock in the tick-tock model. Or maybe it is a tick, like their recent naming schemes, I can never remember which is which. In any case, this derivative wasn't hugely memorable.

Larrabee 3 was going to be a big bang. Intel learned a lot with Larrabee 1, but too late incorporate any of it in Larrabee 2. The third iteration was a different story, it was going to be a 'converged pipeline' model with a massively updated ISA.

If you read this as 'incompatible', well, yes, it was going to be. Luckily, since Intel controls the compilers and dev environment for the chip, a lot of avenues were available to ease that transition. This is being talked about in the past tense because, well, the first chip isn't a public release, so any software that comes out publicly will do so with Larrabee 3, and it will be compiled for that. For now, it is a minor headache for devs at worst.

Since we mentioned Larrabee 3, we should point out that it is now Larrabee 2, currently due in early or late 2012 depending on which sources you put more faith in. Lets split the difference and call it mid-2012, or about two years from now.

The new Larrabee 2 is what the old Larrabee 3 was meant to be, but retargeted to what a high end GPU will be in 2012. Instead of chasing hoping to get the next three generations out less late than the last, Intel just scrapped the timeline, and went back to the drawing board. Specs changed, timelines changed, and all sorts of details were rethought.

Larrabee 3's converged pipeline ISA is now going to be the only ISA the public ever sees. Compiler tricks and dual code path binaries are no longer necessary. When people get their hands on a Larrabee, be it the lucky few who can talk their way into a robins egg blue Larrabee 1, or the new one, the coding path will be set.

In the end, Larrabee was effectively delayed for 3 years, but a lot was learned on both the software and hardware sides. Those who declare the project dead, or say Intel ran away with it's tail between it's legs either have an axe to grind or simply don't understand what happened. Intel is creating a new paradigm, changing the graphics game from the ground up, not just making a GPU. It is a slow and long term process.

The whole converged pipeline CPU/GPU is going to be where both AMD and Intel eventually end up, but their paths are going to diverge near term. Any company that is not aiming for that goal is not going to be in the CPU or GPU game in 3 years because neither will exist as such. Then again, they will have a lot of company in the graveyard of those who fought Moore's law. Two years.S|A

pdfa

market requirment

gz_easy

<<Larrabee comes again>>
A Intel product
Directed by Paul Otellini --- Director of <<Larrabee comes>> & <<Larrabee leaves>>
Coming in November
Featuring Raytracing, TeraScale computing... Only in Lab

红发IXFXI

会不会秒杀cuda？

红发IXFXI

拉拉比议会在未来11

拉拉比3现在拉拉比2
在2012年的收敛性
查理Demerjian

2010年5月17日

英特尔LogoMOST人根本不明白英特尔正在试图与他们拉拉比芯片，英特尔为什么要保持简单地用它去。不过，它并非如许多推测，死亡，甚至受伤，但已经有了一些挫折。

正如有人谁一直关注英特尔的GPU的努力，因为很久以前有人认为他们是真实的，我可以明确表示，英特尔是非常严肃的对GPU的游戏，或者更重要的是后GPU的游戏。经第一次听到在决定赢家和几种不同的微型内核项目的名称拉拉比失败者备忘录。然后，我们开始挖掘到它的设计和它的应有的水平。当我们第一次指出，这是一个基于x86后的图形处理器的芯片，随后的嗥叫不相信笑声。

经过几次示威活动，英特尔的第一个拉拉比拉芯片插头，但没有杀死的项目，由一个长镜头不是。拉拉比，该项目是远远死了，你甚至可以得到一个如果你说服英特尔，你有一个很好地利用它。如欧德宁支持者，你可以确保该项目正在进行中。从什么SemiAccurate的来源一直说，他的支持已经相当强大之前很久以来的路线图改组。

这带来了什么时，我们会得到拉拉比出来的问题，更重要的是，什么时候？简短的回答，融合的管道和2012年。这意味着需要什么背景一点。

当拉拉比最初greenlighted，我们的消息来源告诉我们，那是一个16核心，65纳米芯片，该芯片是为开发商为了得到他们的脚潮湿，不供公众使用。这是一个软件开发种子的一部分，但如果你想手一英特尔现金，他们会拿钱。据我们了解，这部分没有录音，以便于我们将它称为拉拉比0。

拉拉比1，又名你听说过的一部分，数次推迟。因它是不推荐的时间，这是超过一年半晚。第一个正式发布的日期来我们的办法是2008年中期至晚期。

出现的问题。你斧步进是相当粗糙的，很粗糙，业绩不到1 / 4是它的预定目标，并通过权力的屋顶。这些缺陷阻碍了复利问题的发展，并造成严重的发展挫折。问题的根源可能已经找到，但没有固定的，直到它是为时已晚。

于B0步进也解决了大多数问题，但它没有来，直到2009年底返回。这推动了第二季度发布出去约会，基本上现在。对于一个芯片，是针对的图形处理器，一年的拖延HD4870/GTX285一代意味着它会面临HD5870/GTX285中，有一个运动酒吧大增。

由于业绩亏损，英特尔面临着一个艰难的选择，拉动消费的一部分，插头，并采取亲Averbial sh的*批评那些在环，或在不tstorm士兵。当兵就意味着拉拉比2，第3和4将可能被延误，因为资源被转移到拉拉比获得上古出去，英特尔将追逐很长一段时间来它的尾巴。威斯利，英特尔拉了拉拉比1和2插头，以及拉拉比3调整重点。

虽然不能从扶手椅四分卫批评回避，这一呼吁表明英特尔的管理是长期的思维，而不是安抚人民对光泽现在看事情。花了相当多的胆量做了一点，并宣布它公开了，甚至更多。荣誉英特尔那里，他们可以就让它滑，并希望没有人注意到。

这使我们拉拉比2，基本上是刷新和拉拉比1清理。占用，无所适从优化他们能够和修复任何低悬的水果，仍然存在。这是一个在滴答滴答模型笃。或者，也许这是一个喜欢他们最近命名方案剔，我永远记得哪个是哪个。在任何情况下，这不是巨大的衍生难忘。

拉拉比3的将是一个大爆炸。英特尔学到了很多与拉拉比1，但为时已晚纳入拉拉比2的任何。第三个迭代是一个不同的故事，这是将是一个'融合了大量最新的ISA流水线'模式。

如果你读这为'不符'，嗯，是的，它是将要。幸运的是，由于英特尔控制编译器的芯片及发展环境，提供了很多的途径来缓解这种过渡。这是被人谈论过去的紧张，因为，第一个芯片是没有公开发表，所以任何软件，会做出来公开与拉拉比3的话，它将为这一编制。现在，它是一个在最坏的开发者轻微头痛。

既然我们提到拉拉比3，我们必须指出，现在是拉拉比2，目前在早或迟2012年，这取决于你投入更多的资源，只有让信心分裂差异，称之为中期到2012年，约两年后到期现在。

新的拉拉比二是旧拉拉比3的意思是什么，但其重定位到什么是高端GPU将在2012年。而是追逐希望获得下一个三代出比上年底减少，英特尔刚刚取消了时间表，并回到了绘图板。规格改变，时间表改变，种种细节被重新考虑。

拉拉比3的融合管道ISA是现在将成为有史以来唯一的ISA公众看到。编译器技巧和双二进制代码路径不再是必要的。当人们在一个拉拉他们的手，不论是少数幸运谁可以谈成一个蓝知更鸟卵的方式拉拉比1，或新的，编码的路径将被设置。

最后，拉拉比得到了有效推迟3年了，但很多是在软件和硬件两个方面的经验教训。这些申报的项目谁死了，或者说英特尔跑不过来的尾巴与它的腿要么别有用心，或根本不明白发生了什么。英特尔正在创建一个新的范例，改变了从地面图形游戏，而不是仅仅作出的GPU。这是一个缓慢而长期的过程。

整个管线融合的CPU / GPU将是AMD和英特尔在最终结束了，但他们的路径是短期内会出现分歧。任何公司都不能用于该目标瞄准不会将在3年内在CPU或GPU的比赛，因为这样既会存在。再说，他们将在这些谁打摩尔定律墓地的公司很多。两个years.S |阿

garou

ls翻译惨不忍睹～

boyxjg

没看明白.....

sleepyboy

看了机器翻译，突然觉得自己的英文水平远远高于中文水平。