Importance of cache size?

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Hi,

I've just joined this forum but it seems like a great place with a lot of technically-minded people. Which is why I thought it would be a good place to ask a question about CPUs.

I noticed that the cache sizes on AMD CPUs are much higher than Intel CPUs. Is there any reason for this? It would seem like a disadvantage but Intel CPUs seem to be generally better.

For example I noticed that the AMD FX-8350 has 8MB L2 cache and the i7-4770k has just 1MB L2 cache.

Just curious. Thanks! :)
 
Its not just the size, but the location of the different caches that matter and the speed of each section of the cache.
(as well as the caching techniques used, like prefetching, and how they are connected to each other)

Cache helps iterative processes greatly.
ie if something happens repeatedly very often and the operations are small enough to fit into the cache, then they dont need to request data from slower memory/cache, which would increase latency, sometimes greatly.
This means they can be processed at nearer the maximum speed the processor is capable of if the instructions and data fit inside the cache.

The idea is to keep the cpu fed with data/instructions as fast as it can accept.
But another aspect is that CPUs are compared to each others performance and while a CPU with a lesser cache may not be optimally fed with data, it can be fast enough to still eclipse the performance of other processors.

The larger the cache size, the larger the set of instructions and data it can store.
All CPUs can improve their performance through the use of larger cache sizes, but there is a law of diminishing returns.
However, if you cannot get any more performance from the processor itself, you are reliant on how well you keep it fed.
So a larger cache can help a slower cpu keep up with a faster cpu.
 
Intel has much faster caches which makes up for not having as large of a cache.
 
Intel also uses an L3 cache while AMD does not.

AMD also cut the L1 cache size on their CPUs to 1/4 of what it used to be. I still think that that has a whole lot to do with the sucky performance of their current processors vs Intel.
 
cyclone3d said:
Intel also uses an L3 cache while AMD does not.

AMD also cut the L1 cache size on their CPUs to 1/4 of what it used to be. I still think that that has a whole lot to do with the sucky performance of their current processors vs Intel.
Click to expand...

The 8350 has an 8MB L3 cache... and an 8MB l2 cache... that's a pretty big cache. I guess these are cut-down enterprise servers being sold as gaming procs? Sounds familiar. They aren't exactly perfect for the job but they are neat chips and they get by just fine.
 
Bluesun311 said:
The 8350 has an 8MB L3 cache... and an 8MB l2 cache... that's a pretty big cache. I guess these are cut-down enterprise servers being sold as gaming procs? Sounds familiar. They aren't exactly perfect for the job but they are neat chips and they get by just fine.
Click to expand...

Well, that is news to me. Of course I have been out of the AMD loop for quite a while.
 
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