Friday, September 24th 2010
AMD Orochi ''Bulldozer'' Die Holds 16 MB Cache
Documents related to the "Orochi" 8-core processor by AMD based on its next-generation Bulldozer architecture reveal its cache hierarchy that comes as a bit of a surprise. Earlier this month, at a GlobalFoundries hosted conference, AMD displayed the first die-shot of the Orochi die, which legibly showed key features including the four Bulldozer modules which hold two cores each, and large L2 caches. In coarse visual inspection, the L2 cache of each module seems to cover 35% of its area. L3 cache is located along the center of the die. The documents seen by X-bit Labs reveal that each Bulldozer module has its own 2 MB L2 cache shared between two cores, and an L3 cache shared between all four modules (8 cores) of 8 MB.
This takes the total cache count of Orochi all the way up to 16 MB. This hierarchy suggests that AMD wants to give individual cores access to a large amount of faster cache (that's a whopping 2048 KB compared to 512 KB per core on Phenom, and 256 KB per core on Core i7), which facilitates faster inter-core, intra-module communication. Inter-module communication is enhanced by the 8 MB L3 cache. Compared to the current "Istanbul" six-core K10-based die, that's a 77% increase in cache amount for a 33% core count increase, 300% increase in L2 cache per core. Orochi is built on a 32 nm GlobalFoundries process, it is sure to have a very high transistor count.
Source:
Xbit Labs
This takes the total cache count of Orochi all the way up to 16 MB. This hierarchy suggests that AMD wants to give individual cores access to a large amount of faster cache (that's a whopping 2048 KB compared to 512 KB per core on Phenom, and 256 KB per core on Core i7), which facilitates faster inter-core, intra-module communication. Inter-module communication is enhanced by the 8 MB L3 cache. Compared to the current "Istanbul" six-core K10-based die, that's a 77% increase in cache amount for a 33% core count increase, 300% increase in L2 cache per core. Orochi is built on a 32 nm GlobalFoundries process, it is sure to have a very high transistor count.
152 Comments on AMD Orochi ''Bulldozer'' Die Holds 16 MB Cache
instruction prediction, same thing that intel had done long time ago when back to netburst time. such feature only work when you have ridiculous number of pipeline and a trace cache. but despite everything they had done with it they still end up performing pathetic in every benches
The module's front end includes a prediction pipeline, which predicts what instructions will be used next. A separate fetch pipeline then populates the two instruction queues—one for each thread—with those instructions. The decoders convert complex x86 instructions into the CPU's simpler internal instructions. Bulldozer has four of these, like Nehalem, while Barcelona has three.
Each module has a trio of schedulers, one for each integer core and one for the FPU.
This is from techreport and explains just fine. There is no 8kb L1 cache per core. If i am making a mistake please correct me.
And since we have JF-AMD at the forum please explain this clearly!
do you know if AMD will be release 980G chipset ?
and about 8k l1 data....i remember i saw the spec from anandtech three months ago...however i found wiki had 16k l1 cache.....which i'd rather believe anandtech's source...
I understand where your coming from though but for any enthusiast, the stock coolers are just not enough, but then again if they was we wouldn't be very good enthusiast's would we :D
but i suppose i can add this, i still have the old all aluminum heatsink that came iwth the athlon x2 that i am currently readying to be chopped up for other uses so i am greatful for the heatsinks that come with amd processors and am glad they are now heatpipe coolers as even with chopping them up i cam make good use of them.
(no more drunken double posting... at least tonight lol :p)
1. A reporter who has never touched the product
or
2. The director of product marketing for servers at AMD
Choose carefully, there will be a test at the end of the class.