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by PKeeble 6190 days ago
The massive difference in random access speeds in comparison to sequential speeds is the thing that changed in the last 15 years. The gap between memory clock speed and CPU clock speed has been increasing for all this time, whereas prior to that they were often similar.

The impact is that random access has suffered and cache has become vital in coping with the majority of those seemingly random jumps. Algorithms like quicksort benefit from locality of reference and hence better utilise the cache than algorithms that theorectically do less work.

Its interesting to see it jump like this, but its not indicative of large programs so much as it is indicative of what happens when you randomly access memory and effectively nullify your cache and your memorys DDR properties. Thankfully most programs don't in practice do this, if they did the programs would run about as well as they did in the mid 90's on an original Pentium.