Xeon vs overclocked i7 Extreme for lowest latency

cacheintel-core-i7latencyxeon

I am aware that the differences between high-end i7 and Xeon are:

  1. compatibility with dual socket motherboards,
  2. total L2/L3 cache size.
  3. overclocking capability.
  4. extra cores – Haswell i7-4960X vs E7.
  5. power consumption.

(See: What is the difference between an Intel i7 and a Xeon quad core processor?)

What I'd like to ask is, what are the implications of the cache size on achieving the lowest latency?

It seems that I'd much rather have a heavily-overclocked i7 Extreme than a Xeon processor and I cannot envision how an extra 5~15 MB cache will make a significant difference except for a few edge cases where the problem set is too large for the L2 cache and small enough that it doesn't have to rely on main memory. Am I missing some advantage of Xeon processors?

P.S.: We are deploying hardware for neutrino detectors for high-energy physics and need a very fast response time but not large matrix computations. Some will point out that I should be using some ASIC/RISC+RTOS strategy to achieve my goals, but the way the experiments are designed, I just need a 10 microsecond internal latency (hitting socket to egress), which seems possible with regular processors.

Best Answer

Anandtech did a detailed review of the Core i7 4960x recently.

Memory Latency vs. Access Range

But honestly, these times don't mean all that much without knowing what kind of algorithm you're using. Assuming there isn't that much processing to be done, then the ethernet connection is going to be the real bottleneck, like @huseyin said