It has been have found that in many systems the CPU including processor, number of cores, speed, memory etc. (even with identical GPU placed in machines with differing CPU) the benchmark performance will change significantly. How can I decide which CPU will perform best for my ContextCapture hardware configuration?
Intel i7 and some Xeon cards are currently the fastest processors. These have the most number of cores and currently achieve the fastest speed possible. For the same speed and same number of cores, there is no difference between the i7 and Xeon. The i7 can have up to 10 cores, whereas the Xeon can have up to 18 cores with various speeds including turbo speed. However, for the same price, an i7 processor is usually faster than a Xeon processor.
To date we have not tested any AMD processors. However, for various benchmarks, the current AMD processors are slower than Intel ones (which is the main reason we are not testing them).
The number of cores is useful for parallel processes, such as Aerotriangulation and for some parts in Reconstruction step. However, during Reconstruction, there are many parts that run in just a single thread. If we were to count the total power of a processor as: #threads * #speed, then for the same amount of total power, we should pick the processors with the highest speed. For example, in the same generation, a processor with 8 threads running at 3.6 GHz is better than a processor with 12 threads at 2.4 GHz. However, it is possible that a processor of a newer generation is more efficient than an old one having the same speed.)
Dual processors increase the number of cores (and threads). As stated previously the Reconstruction step has many parts which only run in one thread. A dual processor will not be twice as fast as a single, even if we do not take the GPU into account.
A higher thread count is very beneficial for Aerotriangulation and also to a lesser extent for Reconstruction.
Processor speed is very important, especially when we use only one thread. If we “remove” the hard disk access and GPU part, the program runs proportionally to the processor speed.
The i7 processors of last generation, which have 4 cores/8 threads or 6 cores/12 threads and high speed (>3.5Ghz) is sufficient for the current release of ContextCapture.