For Day 18 of the series, we will talk about AMD Turbo CORE technology. AMD Turbo CORE is a technology that was recently introduced in the AMD Phenom desktop processor, but the way AMD is going to implement it in the upcoming Bulldozer family of processors is greatly enhanced. AMD Turbo CORE is similar to Intel Turbo Boost technology in concept (although AMD claims that it works better). According to AMD:
AMD Turbo CORE is deterministic, governed by power draw, not temperature as other competing products are. This means that even in warmer climates you’ll be able to take advantage of that extra headroom if you choose. This helps ensure a max frequency is workload dependent, making it more consistent and repeatable
AMD Turbo CORE allows individual cores in the processor to speed up from the base clock speed up to the TDP level, automatically adding extra single-threaded performance for the processor. Conceptually, it is the opposite of AMD PowerNow! technology. Instead of trying to watch for usage patterns and lowering the processor core speed to try to reduce power consumption, Turbo CORE is watching the power consumption to see how high it can move the clock speed up.
This feature, which is new to AMD server processors, allows individual cores to use the extra power headroom between average and maximum power, turning it into more clock speed. Bulldozer implements a significantly more aggressive version of this capability than the AMD Phenom desktop processor with more details to be disclosed by AMD in the future. Should the processor get too close to the TDP power limit, it will automatically throttle back somewhat to ensure that it is continuing to operate within the specified TDP guidelines. This allows for significantly higher maximum clock speeds for the individual cores.
AMD has stated that Bulldozer will boost the clock speed of all 16 cores by 500MHz, even when all cores are active with server workloads. Even higher boost states available with half of the cores active. AMD has not disclosed how much the clock speed boost will be when only half of the cores are active. When the Bulldozer processor is finally launched you will see processors marketed with a base and a maximum frequency, base will reflect the actual clock speed on the processor and max will reflect the highest AMD Turbo CORE state.
Just like with Intel Turbo Boost technology, I think this is a very beneficial feature that you should take advantage of for database server usage. I don’t see any controversy here (such as with hyper-threading).