4 ms·
I guess a LINPAK Benchmark would be more suitable? http://www.top500.org/project/linpack/ http://www.top500.org/project/linpack/
by diroussel 13y ago
I guess a LINPAK Benchmark would be more suitable? http://www.top500.org/project/linpack/ http://www.top500.org/project/linpack/
- stephencanon 13y agoLINPACK has its own issues as a benchmark; it only exercises extremely predictable floating-point multiply add loops. If a well-tuned implementation of the operation is used (as you see in the scientific computing community), this is representative of the peak arithmetic throughput that the hardware is capable of (so it is a good proxy for raw compute power), but it is still not representative of the way most real workloads (even professional or scientific computing) drive hardware. Even the scientific computing community is slowly starting to move away from LINPACK (see, for instance, http://www.sandia.gov/~maherou/docs/HPCG-Benchmark.pdf http://www.sandia.gov/~maherou/docs/HPCG-Benchmark.pdf). LINPACK as you typically see reported for consumer and mobile devices is far worse; the implementations used there are often naive scalar implementations that do not do any form of cache tiling. This means that for small problem sizes they are actually measuring how clever the compiler is, and for large problem sizes they are actually measuring memory throughput (both of which are interesting, but they are not what a “CPU benchmark” should be reporting). The set of operations covered by Geekbench is actually fairly interesting (with some exceptions). If they simply used the best available libraries instead of their own naive implementations it would almost be a respectable benchmark.
- frozenport 13y agoAlso LINPACK doesn't do IO, which a frequently sets the max speed.
- sjtgraham 13y agoApple also has it's own heavily optimised version of LINPACK available in Accelerate.framework