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0 pointsdfox11y ago0 comments

It depends on what kinds of instructions you count. I strongly suspect that your 3GIps number is only register-to-register integer arithmetic, while the 110GIps is some IBM-ish "mixed workload" that uses most of the System/z instruction set. (which includes things like "get CRC32 of this buffer" as one instruction)

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aries198011y ago· 1 in thread

Average of Dhrystone and Whetstone, which is not a proper benchmark indeed.

Those special instructions such as CRC32 or SHA256 are rarely needed in scientific simulations such as Monte Carlo simulations or real-time working with Bayesian Network, what this system is aimed for. In these scenarios raw power and big on-board caches what matter and on paper the POWER8 has these, but 110 GIPS is not the best bang for bucks.

dfoxOP11y ago

System z is completely different thing from what is currently called Power Systems. Target market for System z is pretty much limited to OLTP and most of the weirdness of the platform comes from the fact that it is heavily optimized for exactly that and not for raw speed in two's-complement or FP arithmetics.

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