CPU comparisons
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Interesting read: https://secure.wikimedia.org/wikipedia/en/wiki/Hertz_Myth[^] What's ironic is now AMD have higher clock rates and lower performance when the opposite was true some generations ago, when they introduced their 'P-Rating', supposedly frequency equivalent in an Intel CPU.
'As programmers go, I'm fairly social. Which still means I'm a borderline sociopath by normal standards.' Jeff Atwood 'I'm French! Why do you think I've got this outrrrrageous accent?' Monty Python and the Holy Grail
How would you try to explain this to normal customers instead of 'more MHz = more good'. Do you really want to lecture everyone on cache levels and sizes, the number of pipelines and the probability of pipeline penalties, the slight difference between the CPU's core frequencies and diverse bus frequencies and such gimmicks as hyperthreading? Indeed, it's traditionally better to compare two CPUs at the same frequency to see what difference the other optimisations make. Simply comparing the frequencies was only a rough measure, even in the days when there were not so many factors to think about. Just how do you compare two different processor architechtures? What would be a fair test? I could always use test code that makes use of one or the other processor's strenghts or weaknesses and simply show what I want the test to show. It's really not much of a surprise that they simplified the whole thing to absurdity by simply comparing frequencies.
And from the clouds a mighty voice spoke:
"Smile and be happy, for it could come worse!"And I smiled and was happy
And it came worse. -
Number of cores and clock rate don't necessarily relate to performance... there's many other factors... 0. Bus rate 1. Bus structure (Intel completely redid the bus structure in i7 CPUs) 2. Instructions per cycle 3. Hyperthreading within cores 4. Number of independent ALUs 5. Cache size/access (old multi-core designs still shared a cache) There are just a large number of factor involved...
Number and size of pipelines, together with the probability of pipeline penalties due to having to wait for an unavailable resource like for example an ALU.
And from the clouds a mighty voice spoke:
"Smile and be happy, for it could come worse!"And I smiled and was happy
And it came worse. -
I have just been looking at a new cpu the AMD Bulldozer range and the flagship cpu is a 8 core 3.8Ghz, yet in a comparison with an i7 2600k quad core the i7 performs better. Can someone please explain to me how this is possible to me reading that just does not make sense!
I don't even look at that anymore. My experience has been that Intel based machines (I usually build my own) last twice as long as AMD machines and I don't do any overclocking on either. For me, twice as long is more valuable than 10% faster.
m.bergman
-- For Bruce Schneier, quanta only have one state : afraid.
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Maximilien wrote:
Me think that most desktop applications do not support more than 4 threads, heck, even 2 threads; so performance will not change much as you increase the number of cores
Given the number of developers I have come across who can't write multi-threaded applications correctly, I doubt much will change in the near future either
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I have just been looking at a new cpu the AMD Bulldozer range and the flagship cpu is a 8 core 3.8Ghz, yet in a comparison with an i7 2600k quad core the i7 performs better. Can someone please explain to me how this is possible to me reading that just does not make sense!
I think i7 has 4 physical cores but 8 logical. At least this is what the task manager on my computer shows.
There is only one Vera Farmiga and Salma Hayek is her prophet! Advertise here – minimum three posts per day are guaranteed.
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What's so hard about it? ;)
And from the clouds a mighty voice spoke:
"Smile and be happy, for it could come worse!"And I smiled and was happy
And it came worse.Go look in the Quick Answers section of CP... you'll see how many people can't seem to figure this out... :laugh:
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Number and size of pipelines, together with the probability of pipeline penalties due to having to wait for an unavailable resource like for example an ALU.
And from the clouds a mighty voice spoke:
"Smile and be happy, for it could come worse!"And I smiled and was happy
And it came worse.Pipelines are quite critical. But you can't teach the common folk that. For those of us that know it though, I recomend never... NEVER EVER EVER, talking with any of the sales guys at ANY of your large PC shops (small shops are more like the "Ace" of PC stores... sometimes). If you do, you will just get upset with them because they will spew out the smoke that they have been dished in and taught to spew out. And if they can't recall they begin making it up (which can screw you if you actually know what you want and they lie about it). Always do your diggin for weeks ahead of the purchase hitting the appriate sites. Ignore the Reviews of "Ohh works so nice." And "Hey I got what I ordered. 5 Stars!!". For those that don't know these details, hire a friend that does. And when I say hire, I mean hire. Tell them you will treat them to a nice dinner (gift card what ever) for their time. Otherwise don't complain.
Computers have been intelligent for a long time now. It just so happens that the program writers are about as effective as a room full of monkeys trying to crank out a copy of Hamlet.
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What's so hard about it? ;)
And from the clouds a mighty voice spoke:
"Smile and be happy, for it could come worse!"And I smiled and was happy
And it came worse.It involves abstract thinking which is not for everybody. Same thing with the pointers and the multiple inheritance.
There is only one Vera Farmiga and Salma Hayek is her prophet! Advertise here – minimum three posts per day are guaranteed.
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I have just been looking at a new cpu the AMD Bulldozer range and the flagship cpu is a 8 core 3.8Ghz, yet in a comparison with an i7 2600k quad core the i7 performs better. Can someone please explain to me how this is possible to me reading that just does not make sense!
Processor Architechure is also very important with frequency speed and number of cores. i.e. Intel's Nehalem Processor has integrated front bus and northbridge while AMD still has these components outside.
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I have just been looking at a new cpu the AMD Bulldozer range and the flagship cpu is a 8 core 3.8Ghz, yet in a comparison with an i7 2600k quad core the i7 performs better. Can someone please explain to me how this is possible to me reading that just does not make sense!
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It involves abstract thinking which is not for everybody. Same thing with the pointers and the multiple inheritance.
There is only one Vera Farmiga and Salma Hayek is her prophet! Advertise here – minimum three posts per day are guaranteed.
Deyan Georgiev wrote:
pointers and the multiple inheritance
I don't use C++ anymore, but most people don't really need to know what they are since they're not doing very complicated programming. Most programming, at least what I've come across, is very simple and mundane compared to what is possible. How much are you going to use pointers as a percent of the programming needed in a website, etc. You're going to write a lot more html than anything else. I'm not saying you shouldn't, just that most don't since its not used as much as other programming. I'd like to see more programmers understand it, but it's not likely. I've heard a lot of theory learning downers and concept downers here.
Well, who doesn't release stuff like that ? Microsoft software is just as bad. Christian Graus That's called seagull management (or sometimes pigeon management)... Fly in, flap your arms and squawk a lot, crap all over everything and fly out again... by _Damian S_
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Deyan Georgiev wrote:
pointers and the multiple inheritance
I don't use C++ anymore, but most people don't really need to know what they are since they're not doing very complicated programming. Most programming, at least what I've come across, is very simple and mundane compared to what is possible. How much are you going to use pointers as a percent of the programming needed in a website, etc. You're going to write a lot more html than anything else. I'm not saying you shouldn't, just that most don't since its not used as much as other programming. I'd like to see more programmers understand it, but it's not likely. I've heard a lot of theory learning downers and concept downers here.
Well, who doesn't release stuff like that ? Microsoft software is just as bad. Christian Graus That's called seagull management (or sometimes pigeon management)... Fly in, flap your arms and squawk a lot, crap all over everything and fly out again... by _Damian S_
C++ is still widely used. This site is mostly enterprise desktop development and web development oriented and is Microsoft centric, areas where C++ stepped out on behalf of more efficient for those tasks languages. But this is relatively small part of the programming world; everything else is still mostly C++. Not my one vote BTW, although I think you’re wrong.
There is only one Vera Farmiga and Salma Hayek is her prophet! Advertise here – minimum three posts per day are guaranteed.
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Deyan Georgiev wrote:
pointers and the multiple inheritance
I don't use C++ anymore, but most people don't really need to know what they are since they're not doing very complicated programming. Most programming, at least what I've come across, is very simple and mundane compared to what is possible. How much are you going to use pointers as a percent of the programming needed in a website, etc. You're going to write a lot more html than anything else. I'm not saying you shouldn't, just that most don't since its not used as much as other programming. I'd like to see more programmers understand it, but it's not likely. I've heard a lot of theory learning downers and concept downers here.
Well, who doesn't release stuff like that ? Microsoft software is just as bad. Christian Graus That's called seagull management (or sometimes pigeon management)... Fly in, flap your arms and squawk a lot, crap all over everything and fly out again... by _Damian S_
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I have just been looking at a new cpu the AMD Bulldozer range and the flagship cpu is a 8 core 3.8Ghz, yet in a comparison with an i7 2600k quad core the i7 performs better. Can someone please explain to me how this is possible to me reading that just does not make sense!
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Deyan Georgiev wrote:
pointers and the multiple inheritance
I don't use C++ anymore, but most people don't really need to know what they are since they're not doing very complicated programming. Most programming, at least what I've come across, is very simple and mundane compared to what is possible. How much are you going to use pointers as a percent of the programming needed in a website, etc. You're going to write a lot more html than anything else. I'm not saying you shouldn't, just that most don't since its not used as much as other programming. I'd like to see more programmers understand it, but it's not likely. I've heard a lot of theory learning downers and concept downers here.
Well, who doesn't release stuff like that ? Microsoft software is just as bad. Christian Graus That's called seagull management (or sometimes pigeon management)... Fly in, flap your arms and squawk a lot, crap all over everything and fly out again... by _Damian S_
If I were to use C++ in a website (not managed C++, the real deal), I would probably use quite a few classes and quite freely use a pointer for every instance I need. This is, of course, a strange scenario as I don't see any reason to do a website in traditional C++. But after having suffered through a Java project and having been stuck with a real cargo cult code monkey squad (with a promise to repeat that experience a few more times), I am actually looking for an opportunity to get out of here and do some real programming again. I have grown a bit tired of the cargo cultists and their grand rules and rituals to actually do very little in a complicated way. How fortunate that C++ seems to be 'in' again.
And from the clouds a mighty voice spoke:
"Smile and be happy, for it could come worse!"And I smiled and was happy
And it came worse. -
I have just been looking at a new cpu the AMD Bulldozer range and the flagship cpu is a 8 core 3.8Ghz, yet in a comparison with an i7 2600k quad core the i7 performs better. Can someone please explain to me how this is possible to me reading that just does not make sense!
This link is in Italian, but in the bottom you have some compile time's comparison in VS2010 on different processors. http://www.tomshw.it/cont/articolo/recensione-amd-fx-8150-bulldozer-delude-la-strada-e-ancora-lunga-risultati-benchmark-produttivita/33899/17.html[^] Cheers!