This is what happens when I take my eye off the ball.

[andrewducker]

Julie recently bought a desktop - and got a quad core processor, which I thought sounded pretty high end.

Until I just went and took a look at processors, and realised that you pretty much can't buy single-core CPUs any more - dabs has three uni-core cpus, versus thirteen dual-core and twenty one with 3 or 4 cores.

Desktops still seem to be maxed out at four-core - but I do wonder how much longer that will last, and whether there's much point scaling beyond that for most people, without something that uses that much CPU, and isn't heavily hard drive dependent.

Comments

[autopope.livejournal.com]

In Apple-world, the top end Mac Pros come in 4-core and 8-core variants. On the desktop, the top end iMac is quad-core; I expect all but the bottom end desktops (20" iMac and Mac Mini) to go quad core within six-twelve months.

There are persistent rumours that the high end 17" Macbook Pro is going to go quad core sooner rather than later.

And Apple got serious about multi-threading/despatch in Snow Leopard with Grand Central and OpenCL. I'd be startled if M$ wasn't moving in a similar direction ....

[andrewducker]

A bit of digging later - the 8-core Mac Pros are dual CPU motherboards, which makes sense. There don't seem to be any 8-core x86 processors as yet.

And I suspect you're right - everything seems to be moving to four-core, which seems to be as high as you can go before the gains vanish (with current architecture, anyway).

Microsoft have their Parallel Library, and are generally making more tools available for producing multi-threaded code. Don't know how it compares with Mac tools though.

[sbisson.livejournal.com]

Next generation processes are kicking in 8 and 12 core devices in the next year, with 16 and 18 a year or so further away.

[andrewducker]

I shall look forward to being proven wrong about how many cores are actually useful to most people.

I'm fascinated by things like Larrabee - 32 cores running together should be excellent for certain easily parallellised tasks (like graphics).

[sbisson.livejournal.com]

It's interesting listening to people like HP's Mark Hurd. He thinks that platforms like Larrabee solve elements of the throughput problem, so what was in the past dedicated hardware becomes software. For HP that means a convergence between the hardware platforms for servers, storage and networking - potentially saving them a lot of money by ramping up the economies of scale across several different product lines.

[andrewducker]

Similar sentiments in the most recent Edge magazine, where the general agreement is that graphics cards are moving from being dedicated tesselators to being ultrafast parallel instruction processors, opening up the options for 3D engines tremendously.

[drainboy.livejournal.com]

With 3 core 360s and 7 SPU PS3s all games are inherently multi-threaded (and all graphics engine are many-many threaded). Most middleware is probably being designed to be a variable, arbitrary number of threads and with lite-threading systems to make use of whatever's available I can see 4 cores just being a stepping stone all the way up. Given that much hardware progression is powered by high-end use, such as games.

[meaningrequired.livejournal.com]

Given that much hardware progression is powered by high-end use, such as games.

Which was the biggest contributor to my shiney new machine :) but the old one took an age to run simple stat program calculations, and the week it was being replaced, died, or at least I believe the motherboard died.

[drainboy.livejournal.com]

Speaking of games, we should really play some WC3 (if you're still playing it) and I can take you and Andy on.

2 vs 1? :)

[poisonduk.livejournal.com]

It committed suicide as you were harshly replacing it after all those years of love - casting it aside for a shinier model!

[sbisson.livejournal.com]

Basically processor technology hit one of Moore's laws walls a few years back. You could put faster processors on your silicon, but they'd just get too hot. The transistor limit is still some way off, so the obvious solution was more, slower and cooler processor cores on one piece of silicon.

That's why core speeds are around 2GHz, peaking at 3GHz, but overall performance/transistor has remained static and will only increasingly incrementally until the next generation of processes kick in in the next couple of years.

[andrewducker]

Yeah - I knew that the frequency wars ended due to technology hitting a wall - and that multiple cores was the answer - but I missed the point where the transition actually happened.

[sbisson.livejournal.com]

It was rather fun at IDF 2006 listening to Charlie Demerjian quizzing Pat Gelsinger about the transition...

[autopope.livejournal.com]

It happened right when Windows Vista shipped.

Vista wouldn't be such a dog if it was running on 4-8GHz hardware. Microsoft seemed to base their hardware requirements on a straight-line extrapolation from the megaherz wars that had been running for the preceding decade ... and fell flat on their face.

[call-waiting.livejournal.com]

I think it's probably fair to say that the distribution of dual and quad core machines is due to the fact that this is what the market wants.

The market, however, does not necessarily know what's good for it. As we learned from the Pentium 4, the market likes to have a number it can use to judge the desirability of a product, regardless of whether or not that number *really* represents a meaningful metric of quality.

Up until now, that number has been clock frequency. I reckon we're starting to see the same effect with the number of cores.

So the market will demand quad- or higher core CPUs even if they can't deliver the sort of performance the consumer expects. Because, frankly, the average desktop user isn't going to be able to tell the difference (because their bottlenecks are always IO, memory or bandwidth to their graphics card) but will be happy because their numbers are higher than the guy next door's.

[andrewducker]

Yup - agreed. When I'm waiting for my PC it's pretty much _always_ for the hard drive.

[sbisson.livejournal.com]

Always buy a 7200 rpm drive :-)

[andrewducker]

Not Fast Enough. And not terribly laptop friendly, from my understanding (feel free to correct me)

I'm somewhat amazed that nobody has produced a drive that's a hard drive with SSD cache attached - it would seem to be the ideal way of leveraging the technology.

[sbisson.livejournal.com]

Actually they have - check out hybrid hard drives. However they really didn't work too well, as the interfaces between drive and SSD were rather lousy...

[andrewducker]

I remember reading about early versions of it - where for some reason it required the OS to know about it, which seemed remarkably odd to me. After all, if it's a cache built into the drive controller why would the OS need to know it was even there?

[call-waiting.livejournal.com]

Ideally, you don't want the SSD to be a simple cache per se, as 1) it would get overwritten a lot, and 2) the SSD isn't necessarily faster than the HDD for continuous accesses.

The idea was that by surrendering control to the OS, they'd be able to make use of OS-level information like global power management: allow the OS to decide what stuff to put in SSD so that it can shut down the HDD and jsut run from the SSD. Good in theory, but in practice, it looks like none of the OS vendors ever bothered.

Theoretically, the drive could profile all this itself, but that would push up the complexity and the cost of the drive.

[call-waiting.livejournal.com]

Yes, Hybrid SSDs made me very excited for a while, and then completely failed to deliver, largely because of the necessary OS support. I'm not 100% sure why they decided to delegate policy to the OS, rather than allow the drive to manage its own storage, but that seems to have been a major contributing factor to their failure.

Also, the decision by MS that the best use they could make of the SSD portion is as save/restore for hibernation...

[andrewducker]

Aha!
http://news.cnet.com/8301-13512_3-10327453-23.html?part=rss&subj=news&tag=2547-1_3-0-5

[call-waiting.livejournal.com]

Interesting link, thanks.

I have to admit I was entirely unaware of ReadyBoost, and am quite tempted to buy a cheapie flash drive to stick in my work desktop machine; but it's seems to be quite hard to find any objective benchmarks on what sort of improvement could be expected, mostly because almost everything I've read in the first page of Google hits is either hand-wavingly high-level ("it makes things faster because flash is faster than an hdd in some way i'm not going to explain") or simply written by complete morons who seems disappointed it doesn't make Quake 5 (or whatever they're up to now) faster.

I may have to actually construct myself some objective benchmarks and try it myself. If only it wasn't for the fact that the only Vista machine I have is my work desktop, so my results would be owned by the company ;)

[andrewducker]

http://en.wikipedia.org/wiki/ReadyBoost#Performance

Looks like it's great if your computer only has 512MB of RAM and a slow hard drive.

Not so useful in a modern PC...

[andrewducker]

Aha!

http://news.cnet.com/8301-13512_3-10327453-23.html?part=rss&subj=news&tag=2547-1_3-0-5

[anton-p-nym.livejournal.com]

I'm looking to convert an unanticipated volume of filthy luchre into a new PC after six years with a 3GHz Pentium 4, and the horsepower available now whitens my hair. Alas, my dream system prices out higher than I want to spend, but I've fallen desperately in unrequited love with the i7 quad-core so I'll keep looking for bargains.

-- Steve's strategy is to buy one rung down from top-of-market and then run the hardware until it's falling apart... saves on the progressive upgrade costs in the long run, and the "shiny!" stays shiny longer too.

[red-phil.livejournal.com]

I think this might interest you.

[andrewducker]

Saw it when it came out - it is fascinating how much things are changing at the moment!

[zz]

ims the intel i7 series have quad cores with hyperthreading, so in theory 8 parallelish threads. more cores is only useful if software's properly multithreaded. advances are slowly being made, mostly in easy win apps like games, but even ff3.5 still often gums up on one thread.