bit-tech.net

Scheduler updates promise Bulldozer performance boost

Scheduler updates promise Bulldozer performance boost

AMD's Bulldozer chip gets a free speed boost, thanks to some Windows 7 hotfixes from Microsoft.

AMD and Microsoft have jointly released a pair of updates for Windows 7 in order to introduce scheduler improvements that make better use of the dual-core module architecture of the Bulldozer architecture AMD FX processors.

Designed to offer competition to Intel's speedy Sandy Bridge and upcoming Ivy Bridge architecture, Bulldozer includes a novel modular architecture whereby each pair of cores share a floating point unit; offering, AMD claims, improved coherency and, thus, performance.

Sadly, the truth isn't quite what was promised: in our comprehensive review of the AMD FX-8150 chip, the first retail Bulldozer unit we could get our hands on, performance was lacklustre at best; coupled with the high price - some £37 more than Intel's Core i5-2500K chip - we were forced to describe what should have been AMD's return to grace as a 'stinker.'

It's a conclusion which AMD is well familiar with: adoption of Bulldozer has been slow, and ours was far from the only critical review around. The company still believes that Bulldozer is the future, however, and believes it knows how to boost those benchmark scores with a new patch.

Backporting scheduler code from Windows 8, a pair of Windows 7 hotfixes aim to improve performance by telling the operating system to stop treating the processor as eight individual cores - to which tasks are assigned at random - and instead treating it as a collection of dual-core modules.

Described by AMD's Adam Kozak as 'similar to the SMT path that the other guys [Intel] use,' the hotfix is joined by another patch which prevents Windows from prematurely shutting down unused cores while there are still threads to be assigned.

'Our testing shows that not every application realizes a performance boost,' Kozak admits. 'In fact, heavily threaded apps designed to use all 8 cores get little or no uplift from this hotfix – they are already maxing out the processor. In other cases, the uplift averages out to a 1-2 percent uplift. But heck, it is free performance, and this is the scheduler model that will be used in Windows 8 - along with some further enhancements.'

One of the two patches is actually a re-release: back in December, Microsoft accidentally pushed the patch live in an unfinished state, with the result that those who had downloaded it were left with a system even slower than before. However, AMD assures us that these patches are the real deal.

While the patches are unlikely to make enough of a difference to change our minds about Bulldozer as a recommended purchase, if you've already invested in an FX chip they're certainly worth a try. Both the scheduler update and the core parking update are available for download now, but it's a manual process; they won't appear in Windows Update.

Are you pleased to see AMD working to improve Bulldozer performance, or is the company spitting into the wind? Share your thoughts over in the forums.

16 Comments

Discuss in the forums Reply
tonyd223 12th January 2012, 12:58 Quote
have you ever seen a cock up as big as this?

AMD, what were you thinking? I've said this before - just die shrink the X6 1100...
yassarikhan786 12th January 2012, 12:59 Quote
I could not care less :/
warejon9 12th January 2012, 13:24 Quote
Quote:
Originally Posted by tonyd223
have you ever seen a cock up as big as this?

AMD, what were you thinking? I've said this before - just die shrink the X6 1100...

Potential reasons why die shrinking the X6 wasn't plausible was they beleived that the arch was getting to old to still improve, also the IMC was struggling a bit as it was worse than the IMC CPC for deneb. If you've seen the video at CES of the new APU using the piledriver core (updated bulldozer) they had a laptop playing Dirt 3 whilst encoding a video and playing another in HD all at the same time.

As far as a worse launch, Pentium D? Also remember intel's first HT cores weren't the best, unless the code was optimised.

However hasn't the launch of bulldozer actually been quite successful for the general computer buyer (not enthusiast)?
tonyd223 12th January 2012, 13:42 Quote
They have discontinued Phenom II units - so a new buyer has little choice for AM3
GeorgeStorm 12th January 2012, 13:46 Quote
Will be interesting to see what kinda improvements, if any, this brings.
Am potentially looking to go Bulldozer

And yassarikhan786, why bother posting then? :/
GravitySmacked 12th January 2012, 14:32 Quote
Quote:
Originally Posted by brumgrunt
Don't expect a miracle, though.

I think AMD will take anything they can get at the moment. I really wish a miracle would happen and give Intel a little cause for concern.
----jimbo---- 12th January 2012, 14:49 Quote
Erm, so treat it more like Hyperthreading then? I'm sorry but it comes across as simply a flawed design, they went after big marketing numbers such 8 core and high Ghz.
.//TuNdRa 12th January 2012, 15:53 Quote
I'll dig through later and compare performance, see if it won't do anything to Geekbench scores and the like while I'm at it.

To be fair; it is two cores. But two cores with only one Integer unit between the two. It only leads to failures because of the sheer amount of shared Cache too, should Piledriver fix those issues; it will do very, very well.
b1candy 12th January 2012, 16:21 Quote
Integer calculation is more efficient than FP, but you need to optimise code (e.g. PI number solvers) to use INT and a lot of programmers will just use FP to save themselves a headache. Hence why the FX-8150 will perform anywhere between a quad core Llano (A6-3850) on FP calculations or an i5-2500K in mixed calculations.
sear 12th January 2012, 18:57 Quote
Hey remember when it was a good idea to go massively parallel for a mainstream-focused processor in a marketplace where heavily threaded applications are confined largely to professional applications?

Me neither.
Madness_3d 12th January 2012, 19:37 Quote
Seriously, I kept the faith AMD and just Meh. Surely at the point at which you saw you were going down the same route as Netburst you should have known this was a bad idea...
alialias 13th January 2012, 01:14 Quote
Incredibly curious as to how well bulldozer is performing in the consumer markets...
fluxtatic 13th January 2012, 07:16 Quote
Quote:
Originally Posted by alialias
Incredibly curious as to how well bulldozer is performing in the consumer markets...

Me, too - in the paper twice a week is a flier for Fry's (computer chain store, for those not in the US). I check it every week just to see what's happening. I haven't seen any BD-based prebuilts ever. Today, though, for dirt cheap, was an Athlon II system. Athlon II! I'm starting to see some A6/A8 laptops, but almost always the prebuilts are Intel - high end is SB, low end is Pentium. Granted, could be some marketing dollar BS happening, too, but what gets put up on sale from the AMD camp is hardly exciting.
l3v1ck 13th January 2012, 14:59 Quote
That's like saying you're going to remove the spare tyre from a Ford Fiesta to improve the performance so it can compete against a Ferrari.
.//TuNdRa 13th January 2012, 20:41 Quote
Bulldozer isn't actually that slow in tests that simply use all cores, so the HT core-parking advantage is negated. It's just terrible in tests that happen to use less than 8 Threads. Ie; Most common workloads. Should Microsoft ever elect to send me the links needed to download these files; I shall install and then test.
azrael- 13th January 2012, 21:27 Quote
Quote:
Originally Posted by .//TuNdRa
Bulldozer isn't actually that slow in tests that simply use all cores, so the HT core-parking advantage is negated. It's just terrible in tests that happen to use less than 8 Threads. Ie; Most common workloads. Should Microsoft ever elect to send me the links needed to download these files; I shall install and then test.

Would this be the two patches in question?

KB2646060

KB2645594


Just noticed you apparently get an email with download links, which is what you're already waiting for... :)

But this and this may be of more assistance.
Log in

You are not logged in, please login with your forum account below. If you don't already have an account please register to start contributing.



Discuss in the forums