Does Cache Size Really Boost Performance?

KyleSTL

Distinguished
Aug 17, 2007
1,678
0
19,790
1
I liked the article, well thought out and short. It draws clear conclusions from a series of tests. I'm a little disappointed you did not include AMD processors in the article, though, since they are the other half of the processor market (let's be real, VIA is a joke in the grand scheme, except in specialized applications). It would be interesting to see how 2x512MB (Windsor & Brisbane) compare to 2x1024 (Windsor) and even 2x256MB (Windsor EE - the 3600+ Windsor). They make processors with those specs that use multipliers of 10 (10.5 in the Brisbane case, which could be lowered, I believe), so it wouldn't be difficult or time consuming to perform these tests, too. Before the flames start, I know Brisbane and Windsor are made using a different manufacturing tech (90nm vs. 65nm), I'm just curious to see how it impacts the AMD procs.

That would have also been helpful, SurJector.
 

Hatman

Distinguished
Aug 8, 2004
2,024
0
19,780
0
Nice read.

More cache = better :D

Although, the gap between 2mb and 4mb was smaller then 1mb and 2mb, both were double.

4mb to 6mb isnt double so the performance imprvoement beacuse of thsi will probably be very small compared to 1 to 2.
 
It looks like the article has a notable flaw...

* briefly puts on nerd cap *

The hypothesis being tested relates to cache ram size. The author did a good job making sure all 3 CPUs were clocked at the same speed. But it looks like the cache ram for each CPU was operating at 3 different speeds.

If I recall corectly, proper scientific method to test this requires that everything else be constant, and that the cache ram size be the only variable. While I don't exactly know how that could be achieved in this test, it would provide truly accurate results.

I have no doubt the differences in cache ram speed skewed the test results a bit. So the results may not be entirely accurate.

* removes nerd cap, stomps it flat, AND sets it on fire, AND extinguishes flames via 'natural' means *
 

annihilator-x-

Distinguished
Oct 8, 2007
14
0
18,510
0
Things would be a bit different for AMD

AMD have always had smaller caches due to manufacturing capacities. The processors from AMD have different designs to mitigate impact of smaller caches. Much of this had been documented very well on Anandtech's in-depth processor architecture reviews.
 

Reynod

Administrator
Wonder how well the Intel and AMD cpu's compare when the L2 cache is disabled ... anyone ever looked at that?

I recall disabling the L2 cache on my old Cyrix box a few years ago and it ran faster ... lol.

I had to flash the mobo from PCCHIPS with a hand torch ... manually ... after peeling off the EE sticker on the window.

Then wind up the spring and reboot (after gently starting the pendulum).

Sorry ... I'm being too technical ... heh heh.

The nurse is coming with my medication now ... gotta go :)

 

prodystopian

Distinguished
Jul 7, 2006
259
0
18,780
0
I would like to see the results for the AMD CPUs. I would also like to know why the authors decided to forego the AMD CPUs for this test.

The results are surprising and I will keep this in mind when I purchase a new processor in the coming months,
 

ragemonkey

Distinguished
Jun 26, 2006
186
0
18,680
0
The article is flawed and biased. I find it strange that the benchmarks that the author posted directly contradict his conclusion. One would think, that if the real world numbers were truly that much different, he would've posted those results, and not ones where it showed, in many cases, less that a 10% difference from top to bottom. Instead he just says, look at the CPU charts... I'm right. OK... but the numbers you just posted say different... huh? It just seems this article is a bit biased, as the author obviously was trying to prove a point up front, then posted data that directly contradicts his hypothesis, then backtracks in his conclusion by using a nebulous reason as to why he is right. Also, the author manages to skew his findings by only using Intel chips that still rely on the FSB. If he had used any AMD chips, one would see that an Integrated Memory Controller puts far less importance on L2 cache than the use of a FSB. I would've liked to have seen a AM2 6000+ Windsor put against a AM2 5000+ Black Edition Brisbane @ 3.0ghz to see the difference between 2x512kb and 2x1MB. But doing so would only further debunk the author's hypothesis.
That being the case... why did he even bother writing the first 7 pages? He could've just written page 8 and the article holds the same weght.
 

trinix

Distinguished
Oct 11, 2007
197
0
18,680
0
Amd has too many variables I think to test it out. There are a lot of differences between them.

Still it would be interesting to see how AMD fights with it's lower cache size and in a few weeks/months how the L3 cache works for the phenom line and the tricores too (if they keep the same L3 cache even though they are losing a core)

The cache size and speed is an interesting subject, I hope we will see more of these.
 

ragemonkey

Distinguished
Jun 26, 2006
186
0
18,680
0
That is true, The Brisbane core has an added latency that the Windors do not, which would skew the test... even if ever-so-slightly... it would still not be completely accurate.
 

GloriosoSLB

Distinguished
Jun 5, 2006
59
0
18,630
0
“However, the most important benefit is due to how Intel can offer more processor variants with 6 MB, 4 MB, 2 MB or even 1MB L2 cache. In doing so, Intel utilizes an even higher percentage of the dies on a wafer despite some scattered defects that might have forced Intel to throw dies away in the past. “

Funny that’s exactly the same advantage that AMD native quad core has, you can make triple, dual and single core CPUs out of the quad core.
 

KyleSTL

Distinguished
Aug 17, 2007
1,678
0
19,790
1
@ragemonkey: The author said that there is a performance difference in the three cache sizes. This is a fact. He did not go into the debate of what percentage increase that translated into and whether or not it made financial sense, simply that more cache increased the performance of the system. Stop flaming him. It is up to the reader to decide whether an ~10% increase in performance is worth the money. The general investigation was whether the amount of cache changed the system's performance, or whether clock speed alone determines the level of performance; and conclusions were made that fit the data that was gathered.
 

eltoro

Distinguished
Dec 31, 2007
69
0
18,630
0
I am the only one thinking that the only benchmark result that really mattered was WinRAR, and that the difference in games was at such high frame rates that a smooth game play was archived anyway???
I'd challenge the author to try to show that different cache sizes could mean the difference between a smooth game play and a choppy one. Improving your frame rates from 167 to 175 only awards you with boosting rights, which in my account is pretty infantile.
 

KyleSTL

Distinguished
Aug 17, 2007
1,678
0
19,790
1
@eltoro: You forget that little bit of performance you pay for now could pay dividends when more resource intensive games come out (like 35fps vs 40fps). Buying the largest cache is more for future-proofing than anything else.
 

True but cache must not be overestimated at the cost of higher clock rates. The more cache you have the more heat and the more heat you have the lower clock rates will be. More cache you have the less room for processing structures and less cache you have the more room for processing structures.
 

Slobogob

Distinguished
Aug 10, 2006
1,431
0
19,280
0

Almost 20 lines without any information or factual points regarding your own argument. A little more quotations, better formating and punctuations would make your argument easier to understand.

You begin with the conclusion instead of outlying a proper argumentation. Instead of quoting the author you go on and spin your own twisted review trying to impersonate the original author coming to the very conclusion you drew out in the first sentence. Basically you do yourself what you are trying to complain about.

Your finding "that an Integrated Memory Controller puts far less importance on L2 cache than the use of a FSB" is interesting yet you fail to provide factual information. Claiming something based on personal feelings or subjective observation does not equal facts. Stating information as a fact does not inherently make it a fact.

While you state that you would have liked to see how other Processors would have acted with different sizes of L2 cache, especially processors with a build in memory controller, you only provide speculative arguments why the author didn't provide that information in his review. Someone interested in a serious argument would have at least tried to see reasons why the author did or didn't include it. You only provide speculative reasons that benefit your own conclusion that is based on your subjective perception of the article.

Since you are unwilling to even see arguments leading to a conclusion different from your own, i conclude that you made up your mind before you read the article.


If i'm wrong and simply failed to comprehend your argument i sincerely apologize and hope you are willing to point out my misunderstanding in a comprehensive way.
On the other hand if you are a "fan" or emotionally attached to a certain brand and simply try to propagate your own personal views as facts or to provoke others, please refrain from posting.
 

eltoro

Distinguished
Dec 31, 2007
69
0
18,630
0
@KyleSTL: lets try a little math...
For example, Quack IV:
174.6 / 167.7 = 1.0411 = 4.11% performance improvement between 2mb and 4mb

lets apply this to a game running at 35fps with a 2mb cache CPU, and we'll get 35 * 1.0411 = 36.44fps

Now, that's hardly an improvement that even deserves the time and attention I'm taking to write this reply. This won't realistically and noticeably improve choppiness.
 

zenmaster

Splendid
Feb 21, 2006
3,867
0
22,790
3


But much of that is not totally relevent to the article or the conclusions made.

1) In regards to processing structures - This would require Intel to maintain totally difference CPUs. In this case we are dealing with identical CPUs, but with optionally different amounts of cache. The E2160 has no more processing structures than the E6850.

2) More Cache does not always mean better OCing. The E6750 will OC much higher than any of the E2xxxx chips due to the newer stepping. Yes, more cache may more more heat with everything held constant. But again, the point of the article was not which CPU could OC the highest or the cause of that.


 

ASK THE COMMUNITY

TRENDING THREADS