TPS Rep...err PRS Documents

At ATI there’s a document called the Product Requirement Specification, PRS for short. It was originally a big text document written in Microsoft Word.

The purpose of the document is to collect all of the features that have to go into the GPU being designed, and try to prioritize them. There are priority 1 features, which are must-haves in the document. Very few of these get canned. Priority 2, priority 3 and priority 4 features follow. The higher the number, the less likely it’ll make it into the final GPU.

When Carrell Killebrew first joined ATI, his boss at the time (Dave Orton) tasked him with changing this document. Orton asked Carrell to put together a PRS that doesn’t let marketing come up with excuses for failure. This document would be a laundry list of everything marketing wants in ATI’s next graphics chip. At the same time, the document wouldn’t let engineering do whatever it wanted to do. It would be a mix of what marketing wants and what engineering can do. Orton wanted this document to be enough of a balance that everyone, whether from marketing or engineering, would feel bought into when it’s done.

Carrell joined in 2003, but how ATI developed the PRS didn’t change until 2005.

The Best Way to Lose a Fight - How R5xx Changed ATI

In the 770 story I talked about how ATI’s R520 delay caused a ripple effect impacting everything in the pipeline, up to and including R600. It was during that same period (2005) that ATI fundamentally changed its design philosophy. ATI became very market schedule driven.

ATI's R520 Architecture. It was delayed.

The market has big bulges and you had better deliver at those bulges. Having product ready for the Q4 holiday season, or lining up with major DirectX or Windows releases, these are important bulges in the market. OEM notebook design cycles are also very important to align your products with. You have to deliver at these bulges. ATI’s Eric Demers (now the CTO of AMD's graphics group) put it best: if you don’t show up to the fight, by default, you lose. ATI was going to stop not showing up to the fight.

ATI’s switch to being more schedule driven meant that feature lists had to be kept under control. Which meant that Carrell had to do an incredible job drafting that PRS.

What resulted was the 80% rule. The items that made it onto the PRS were features that engineering felt had at least an 80% chance of working on time. Everyone was involved in this process. Every single senior engineer, everyone. Marketing and product managers got their opportunities to request what they wanted, but nothing got committed to without some engineer somewhere believing that the feature could most likely make it without slipping schedule.

This changed a lot of things.

First, it massively increased the confidence level of the engineering team. There’s this whole human nature aspect to everything in life, it comes with being human. Lose confidence and execution sucks, but if you are working towards a realistic set of goals then morale and confidence are both high. The side effect is that a passionate engineer will also work to try and beat those goals. Sly little bastards.

The second change is that features are more easily discarded. Having 200 features on one of these PRS documents isn’t unusual. Getting it down to about 80 is what ATI started doing after R5xx.

In the past ATI would always try to accommodate new features and customer requests. But the R5xx changes meant that if a feature was going to push the schedule back, it wasn’t making it in. Recently Intel changed its design policy, stating that any feature that was going into the chip had to increase performance by 2% for every 1% increase in power consumption. ATI’s philosophy stated that any feature going into the chip couldn’t slip schedule. Prior to the R5xx generation ATI wasn’t really doing this well; serious delays within this family changed all of that. It really clamped down on feature creep, something that’s much worse in hardware than in software (bigger chips aren’t fun to debug or pay for).

Index The Other Train - Building a Huge RV870


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  • Stas - Sunday, February 14, 2010 - link

    Awesome. Thanks! Reply
  • Adul - Sunday, February 14, 2010 - link

    Really helps pass the time at work today. :) Keep it up.

    Btw when can we expect to see the new site launch?
  • aapocketz - Sunday, February 14, 2010 - link

    [quote]I was convinced that ATI had embraced a new, refocused approach to GPU design, only to learn that they nearly threw out all of the learnings with the RV870. [/quote]

    It sounds like they have had some successes trying different techniques, but without stability in their production process it is hard to repeat success. I understand that they require constant innovation to stay competitive, but throwing out whole processes seems chaotic to me. I would like them to refine and improve successful processes rather than toss everything every time a new business guru is in charge.

    Also half of their effort was all about openness and collaboration. The opening up of the PRS document so that "everyone was involved in the process" seems to clash with the hyper-secret groups where "AMD has since incorporated much of Carrell’s brand of information compartmentalization into how it handled other upcoming features." This seems like a recipe for disaster to me. Which is it, broad openness, collaboration and consesus; or secret teams that have no idea what the other teams are doing?
  • SuperGee - Sunday, February 14, 2010 - link

    The story told us that they didn't know it will become a succes because these desision where made before RV770 release. So doing the high risk choice again. Wasn't a nobrainer. But a risky choice. We know that it turn out good now. Reply
  • mckirkus - Sunday, February 14, 2010 - link

    It's kind of funny that you're not yet running one of these companies yet Anand.

    One of the reasons I check this site on a daily basis is because you also seem to also get the business side of the equation. It's downright refreshing to see someone bridging that gap. You pretty much saved the Vertex from self destruction. I'd like to see what interesting things you could build us if you put your mind to it.
  • deputc26 - Sunday, February 14, 2010 - link

    Articles like these are what differentiate AnandTech from all the other sites out there. AnandTech goes from being one of the best review sites out there to something special.

    Beyond excellent, thanks Anand.
  • rickyv - Sunday, February 14, 2010 - link

    As a loyal follower of your website for the past 15 years, I also felt that I just had to register and compliment you on an excellent article.

    With the rapid advancement of technology, it is very easy just to get caught up in the PR and marketing hype or focus only on the numbers game. We often lose sight of the fact that it is teams of dedicated people who make this possible. You have always had the ability to bring out the "human" side to this. I have not seen this on any other site nor in printed form (that is not an unashamedly PR marketing exercise).

    Thanks for staying true to your roots by giving honest opinions of the technology that you review. The latest releases are not necessarily always the greatest (as much as the marketing departments would like us to believe :-) )
  • krish123 - Sunday, February 14, 2010 - link

    After i read the article, I found that "Engine is running well and firing on all the cylinders", It can create better products in the future, I can trust and buy ATI products, hope they deliver better products in the future for my upgrade.

    "Kudos to Anand for the excellent article".

    By the way graphics card is a product, not just hardware, it has to work in tandem with the software, its better ATI put some more effort on the driver/software side and fix all the issues.

  • smartalec - Sunday, February 14, 2010 - link

    "When companies like AMD and NVIDIA do a product the engineers don't know all of the answers, and the knowledge they do have isn't binary - it's probability, it's weight, it's guesses. Sometimes they guess right, and sometimes they guess very wrong. The best they can do is to all weigh in with their individual experiences and together come up with the best group of guesses to implement."

    I'm afraid this is how all engineering works. Project managers think that engineers can predict the future. That we know exactly how much time it'll take, and how much risk a given feature will bring.

    We don't. There's a lot of educated guesses. Sometimes we're pleasantly surprised that what we thought was a tough problem wasn't. Sometimes we're the bearer of bad news-- something we assumed would be trivial wasn't.

    My most frustrating issues aren't technical at all. I ask for 2000 hours, and are given 1000. Or are given 2 engineers instead of 3, and told-- figure out a way to get it done anyway, without impacting schedule.

    Great article Anand.
  • mckirkus - Sunday, February 14, 2010 - link

    Any decent project manager (I do software) reviews the risks up front with the engineers before building the project plan / timeline.

    The fact that most project managers don't really understand the products they manage is the rule not the exception. The problem is that great engineers don't always make great PMs. Having a good tech lead helps.

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